Consumer Perception of Modern and Traditional Forms of Advertising

If a company wants to succeed in a tough competitive environment, it must consider all the options to be more visible. One of these possibilities is advertising, which exists in a considerable variety of forms. Therefore, our goal was to conduct a survey on the attitude of customers in Slovakia to several modern and traditional forms of advertising, which are used by companies for their visibility. Data were obtained from the questionnaires filled in by 244 respondents. We were interested in opinions on advertising oversaturation, the influence of advertising, annoyance by advertising, and credibility of advertising. In each of four topics, we investigated opinions on 21 different types of advertising, using non-parametric tests to determine the significance of differences, which means we used inductive statistics. According to respondents, the advertising on social networks has a higher influence than most other types of advertising. At the same time, it is not one of the most trusted forms, nor one of the most bothering forms. The right marketing strategy choice concerning time, money, form, and efficiency is a key factor to companies. Therefore, it is important for companies to use the right form or combination of forms of advertising to make themselves known depending on the type of product and its target group. To increase the sustainability of a company in the market, it is important to use the right form or combination of forms of advertising considering the product and the target group.


Introduction
Changes in socio-economic conditions in countries result in their economic and social process management changing [1], which is also reflected in the business sphere. Many changes in science and research, and innovations in technology and knowledge, brought new perspectives on the world with an emphasis on creativity, efficiency, innovation, social benefits, and economy. The cohesion and effect of these influences is also visible in the field of marketing [2]. In the context of technological, socio-demographic, and urban development changes, there is a change in customer behaviour concerning the spending of free time, shopping, travelling, etc. [3]. The companies should be able to adapt to these changes.
In the contemporary market, firms use not only new ways of providing services and organising trade, but also new ways of communication with customers [4], for example using social networks.
Constant change is the main feature of the present times, to which the marketing managers of companies must also respond. Natural and unforced activity of customers on social networks has forced marketing experts to make radical changes to marketing communication. Change of customer behaviour naturally leads to changes product promotion and presentation [5].

•
Firstly, is the difficulty of determining the rate of return on investment in brand promotion; that is, assessing (financial) sustainability performance and the profitability of marketing [11]. The economic dimension of sustainability is the most desirable according to Gupta, Kumar, because it provides financial strength and avoids conditions leading to an early demise of the business due to financial reasons [12].

•
The other problem is the issue of non-financial environmental and social sustainability performance. Business organisations are expected to utilise their available technological resources to pursue profit-with-purpose by maximising the return on shareholders' investment, while also achieving social and environmental gains. It is therefore important to identify the value added by individual marketing activities in terms both of investment returns and non-financial sustainability enhancement [11].
One way for companies to balance both kinds of sustainability might be through the careful selection of marketing activities, based on their achievements in terms of user engagement. Market-based measures complement accounting measures by providing deeper insights into corporate performance and incorporating future performance expectations [13].
The results of worldwide research on small and medium sized businesses, conducted by experts from the European Commission, referred to unpredictable market conditions as one of the major external challenges for the overall sustainability of the small and medium-sized enterprises sector across Europe [14]. Companies are more and more required to be responsible and accountable, and this puts increasing pressure on businesses to implement sustainability practices, in order to contribute to sustainable development goals [15].
Several specialised articles have conducted surveys on the influence of various forms of advertising on customer behaviour and decision-making, or have dealt with the analysis of individual social networks [16][17][18][19][20][21]. Others have determined social media goals, the importance of sustainability, and the creative elements of digital promotion [22][23][24]. Several articles have dealt with the influencer marketing, media communication, and sustainability [5,25,26]. Several other studies have addressed similar topics, but have been carried out in different countries. In Malaysia, for example, the impact of online advertising on the younger generation under the age of 35 has been examined [27]. In China, the impact of the traditional advertising medium (television) on the young generation has been studied [28]. In India, the impact of advertising on Tweenagers (Tweenagers are children between 8-12 years old) has been investigated. The researchers examined traditional forms of advertising (television), as well as newer ones (online gaming sites, social networking sites, mobile chatting, online shopping sites) [29]. In Korea, social network services and social media advertising [30] was assessed. In Pakistan, the impact of emotional advertising, online advertising and repetitive advertising on customer shopping behaviour was examined [31]. There are many differences between countries in terms of culture, customs, traditions and so on, therefore it is unlikely that the results would be the same in the Slovak Republic. Consequently, we considered it sensible to carry out detailed research.
According to information available, only a few authors have dealt with the customers´perception of advertising. Authors Pikas, B. and Sorrentino, G. dealt with the customer perception of online advertising, for example. According to these authors, customer perception of online advertisement is deteriorating, and advertisers start to question efficiency of social media advertisements and understand that a constant flood of intrusive commercial information is no way to guarantee customers' attention [32]. Authors Hung, Li and Tse suggest that social media networks are perceived as less persuasive than traditional marketing communications [33]. Nevertheless, authors Poornima, Saumya and Umesh found out that 89% of respondents are influenced by online advertising very much in their study [34].
Within this context, we analysed the attitude of customers in Slovakia to different forms of advertising. To obtain an overall picture of consumers' perceptions of advertising, the research included modern forms of advertising (e.g., advertising on social networks, webpages, via e-mail, etc.), but also traditional forms of advertising (e.g., television, radio, leaflets, etc.) that used companies in the Slovak Republic. We did not find such complex research when studying the sources available. This knowledge can be valuable for companies to enforce their sustainability in the market. It can help them to aim their promotions more effectively towards the target group of customers with additional regard to financial sustainability. The right choice of the suitable form of advertisement enables companies to win the attention of the wider audience and positively influence customers´behaviour at the same time. It is considered the base of the lasting competitive advantage and is decisive for the sustainability of the company in the market. Specifically, in this article we dealt with: • Which forms of advertising do respondents consider to be the most oversaturated? • Which forms of advertising have the greatest influence on respondents? • Which forms of advertising do respondents consider the most annoying? • Which forms of advertising do respondents consider the most reliable?
We were also interested in differences according to age and gender of the respondents.

Theoretical Background
Corporate sustainability has various dimensions, namely economic, environmental, social, and companies are required to pay attention to all these dimensions to meet stakeholdersé xpectations [35]. Sustainability is a challenging task for companies as they struggle for profit while considering the impact of their operations on society [36]. This challenging task has some significant costs for companies, but is accompanied by bringing some advantages.
One of the basic aims of all companies doing business in the present market environment is to be different from their competitors [37]. In order to notice a company and buy its product or service, the customer needs to obtain a lot of information. Based on references from our acquaintances, it is possible to obtain information not only about a specific product or service, but also about their quality. This method of advertisement is considered the most reliable [38]. Different types of advertisements can be used by companies to promote themselves as well as their products. That can be more modern advertisement forms on the internet or more traditional forms of advertisement such as on television or radio, outdoor advertisements, or advertisements in print media. According to Efstathiou [39], traditional media are used for branding, and to action a sales promotion to drive revenue generation and profitability. Despite this, TV advertising is considered to have little influence on the customers; although it has been proven, that if it captures their attention, it can trigger further information research, often leading to a purchase decision [40]. Results of the study by Efstathiou indicated that radio advertising has the most significant influence on the customers. Radio advertising is a platform which has been used by brands, products, and services since 1922 [39]. The results have shown that participants who previously listened to the radio advertisements spent a longer time looking at the brand and had a higher engagement when watching the same advertisements on television. Moreover, they had a different kind of visual attention to the website banners. This pattern of results indicates the effect of mere exposure-that is, the exposure to a radio advertisement enhances the effectiveness of the same advertisement via television or web, offering useful insights for media planning campaigns [41]. Regarding outdoor advertisements, consumers can be exposed to outdoor advertising through a variety of ways, and their purchase behaviour or decision-making may be inadvertently influenced by such exposure [42]. It is a great mistake to think that advertising should take place only on the internet today. Outdoor advertisement, e.g., on billboards, buildings, posters, and means of public transportation can bring the desired effect for the companies, as long as it is implemented professionally and at a high quality. Its influence of 24 hours a day, 7 days a week is a great advantage and it does not make the impression of a permanent intrusion. The attention span of internet users is very short, and hardly anyone watches all the advertisements displayed. Moreover, advert blocking software is utilised by many users online. Billboards, on the other hand, can be granted more attention if noticed and the brand advertised can be remembered with a greater probability. The basic marketing rule of "The Holy Trinity" is often mentioned. Accordingly, the products 'get under one´s skin' when noticed three times. Outdoor promotional areas are noticed many times daily, when people pass by on the way to work or school. People are exposed to the same outdoor advertisement more times, which increases the assumption of remembering the brand [43].
It is important to understand customers to increase the effectiveness of the advertising. Advertisers must know them and know what "works" to influence them. Companies need to know their values, desires, wishes and so on [44]. It is important to attract their interest and attention. It is the first step to make them start thinking about the need for a product or service. It should be noted that each customer is different and receives and reacts to information differently. This depends on various aspects, and influences how the consumer responds to the information. They can be of psychological, cultural, or social character. The customer's interest in a product or service also plays an important role [45]. Thanks to advertising, the company gains several benefits. In addition to the sales increase, it can also reach new customers and extend its market.
"Finding what to tell recipients is the beginning of communication with them, but how to say it is important for the statement being accepted and trusted" [46]. Therefore, creating an interesting advertisement means gaining a customer´s attention and entering their subconscious to achieve memorisation and encourage a final decision. Advertising can act as a stimulus; this stimulus is perception. It is necessary to have knowledge not only from the field of economics and marketing, but especially from the field of psychology [47]. Many people think that psychology and advertising have nothing in common, however they focus on the most important "the person-the customer". Knowing the customer and presenting all the important information as to the benefits of buying a particular product is the key to successful advertising from the marketing point of view [46]. The psychology of advertising deals mainly with the effect of advertising on a person, his emotions, the area of neuromarketing is important in practice and the ethical aspect in advertising is equally important [48]. The most successful advertisements in human history have been able to influence customers´behaviour, stay in their heads and increase sales. The pattern of customer behaviour is used in the creation of advertisements, using psychological tactics. Each high-quality advertisement has at least one of the five psychological tactics [49]: • Creativity based on emotions-Emotional and psychological stimulation resonates with customers much more than highlighting the functionality and features of the product. The influence of a product on the customer´s life is the key factor, not how the product works or why it is different compared to its competitors. Authors Pansari and Kumar [50] state that achieving customer satisfaction is not enough, and, in order to gain a sustainable competitive advantage in building relationships with customers, a company needs to arouse the emotions that lead to commitment. Thus, business objectives extend beyond customer retention to customer relations based on engagement, the promotion of which makes it easier to balance financial and non-financial corporate sustainability goals. (e.g., Snickers, "You're not you when you're hungry").

•
Focus on shortcomings-Customers question marketing claims. Often, marketing claims are not even believable. If a company wants to increase the credibility of a product, it is suitable to point out its shortcomings. Honest and transparent communication can improve the communication of a product's value of a sustainable business to customers. (e.g., Volkswagen created their market by admitting that their car is small at the beginning of the advertisement.) • Change consumer perception (repositioning)-it is necessary to change the position the product has in the mind of customers. For example, pointing out that a given product is better, more delicious, more scented, etc., than the competitor. There are several senses involved in advertising, such as smell, and taste. These are suitable to employ when promoting food, laundry detergent, air freshener, etc. • Encourage exclusivity-People want to feel important. They want to be part of a luxury and exclusive group. Sometimes, it is also possible to appeal to the sense of rareness. This is why advertisements sometimes make statements such as: "We are not for everybody." Exclusive products such as cars and jewellery are often communicated this way. (e.g., An American Express advertisement with Beyonce says, "She has no time to lose, that is why she shops online." At the end, they ask: Are you a cardmember?) • Fear, uncertainty or doubt and an offer of solution-Fear, uncertainty and doubt are often used by companies to slow down customers and make them think about their behaviour. It is used for more serious topics and for communication with a large number of people. This should be done with caution, however, because many customers do not want to be surrounded by negative messages, or even think about them. The goal of these advertisements is to shock and change behaviour, even through absurdity.
Customers are confronted with a lot of advertisements every day. That is why it is important for companies that their advertisements enter the subconscious of the customers. Otherwise, the advertisement will not be comprehended by the customers at all. One of the five psychological tactics can be used to plant an advertisement in the subconscious of the customer. The main significance for applying them consists of raising the interest of customers, manipulating them customers to increase sales, which can help the sustainability of the company in the market. The perception of advertising also depends on its psychological aspects. In the case of cosmetic promotions, as Cieslik Sylwia [51] states in her research, products promoted using advertisements with negative emotions in the form of uncertainty were perceived as the best; products promoted in funny advertisements were viewed as the worst, according to the author [51]. Therefore, it is important to consider which emotion the company wants to arouse.
The customer can also be captivated by catchy music, unique voices, interesting shapes, striking colours, dynamic movements, and the selection of suitable personalities, among other factors. Ideally, advertising should be able to attack several senses [46]. Attractive or famous people influence customer preferences, which influences the purchase decision [52]. However, it is recommended to consider the purpose of advertising campaigns carefully. If the aim is to form an attitude, choosing a celebrity as the advertisement spokesperson is suggested; however, if the aim is to raise the awareness of the brand, choosing a non-celebrity spokesperson is more beneficial [53]. It is important to keep in mind that without a sufficient dose of emotions (whether positive or negative), advertising will not attract attention and interest, even in the case of a quality product [46]. Trust is a factor also worth considering for two main reasons. Firstly, trust must be in place if advertising is to serve as an information source, which means that it fulfils its basic functions. Secondly, there is a constant tendency of consumers to distrust advertising. To close the gap, companies are testing various ways of how to influence customer perceptions of advertisements and how to relate to their values [54].

Internet Advertising
Contemporary customers are more experienced than ever, therefore common advertising does not influence them as effectively as in the past, and their requirements for products and services satisfying their needs are higher and higher. Markets are saturated meaning competition is high, offers are higher than the demand, and advertising is less efficient the larger its costs grow. Due to this, there is a need to implement new forms of marketing communication [55] using new technologies and media, such as the internet, for example, to communicate with customers [56].
Internet advertising incorporates new platforms and business opportunities for companies and brands, and significantly influences users' attitudes and intentions to purchase [57]. Negative or positive observations of a product or service, which were previously limited to a small environment, spread on the internet and can impact millions of people [58]. The internet has become an essential tool for users in the decision-making process, enabling them to search for information on products and services, to compare and review alternatives, and to make final decisions [23]. With the development of internet advertising technology, the adjusted targeted advertising based on user preferences is more suitable both for the market and users [59]. The advantages of internet advertising can be [60]: • The targeting of a wide range of consumers.

•
Lower financial costs compared to advertising that is offline in nature.

•
More simple and accurate measurability of advertisement based on various analytic tools.
Disadvantages of internet advertising can be [61]: • Necessary technical expertise. The company needs a qualified employee who controls computer networks. With this employee, there are associated higher labour costs.

•
Customers can avoid unwanted advertising on the internet and use ad blockers.

•
The older generation, who do not use internet so much, are more difficult to reach by internet advertising.
With the rapid development of the internet economy, internet advertising has become the main advertising channel. The core of advertising is to discover the most appropriate advertising strategy for the combination of users and the context to increase the overall advertising profit [62]. Smart internet marketing can make marketing communication more effective and the company goals can be reached easily [63]. With the development of the internet, the web has become the preferred medium for businesses to promote their products and services. The modern business world has become digitalised and people prefer to make purchases online; which is considered to be an easier, faster, and more convenient process than traditional modes of shopping [34]. In connection with that, it is necessary to support the credibility of the websites. One of the easiest ways of gaining trust is to apply the credibility factors on the websites. Protection of personal data, certificates of quality, and the SSL protocol ("https" at the beginning of the URL address) can be included among these factors. Further factors increasing credibility of a website are the time of loading (ideally 2-5 s), design of the website, visible contact data, information on products with pictures showing good quality, and reviews. Regular updates are also important. Increased credibility offers a significant competitive advantage to the company [64].

Advertising on Social Networks
Advertising on social networks has come to the fore. Social media is one of the most promising tools in the digital advertising environment [65]. It is a set of online communication channels built on community-based input, interaction, content-sharing, and collaboration. These include social networks´websites, video sharing platforms, blogs and micro-blogging platforms, forums, and messaging platforms. Unlike traditional broadcast channels, social media channels are two-way communication platforms that enable people to respond and react to information [66].
The increase in advertising on social networks has accelerated because the number of users of these networks has increased [58]. Social networks specifics are [67]:

•
Representative of a space for conversation.

•
They provide the ability to share content. • They offer space for publishing content created by their users.

•
They support the mutual participation of users in content creation.
The combination of these features then gives space to activities and functions such as building relationships, distributing user-generated content, rating and tagging of content, and of course, fun.
Regarding user content, it should be noted that this is not only written content, but also photos and videos [67].
We are now living in a communication environment with increased personalisation and mobility. demographic parameters provides space for highly effective Social network services (SNS) are spreading rapidly around the world, and enterprises are increasingly using SNS to attract customers and communicate with them [68]. This increases access to brand/product information, thereby turning the information search into a key stage of the shopping decision process [69]. Features commonly offered for marketing purposes by social networks are a serious and important advertising channel, which enables the targeting of marketing activities very precisely. The possibility of precise targeting based on relatively accurate socio-advertising campaigns [67].
Social network services (SNS) advertising is frequently utilised by enterprises to communicate with customers because it provides the best marketing effect using low-cost media. However, the value of SNS is increasing, so managers need to look for more effective methods of utilising the existing SNS channels [70]. Within marketing, social networks can be used to reach these goals [67]: • Building public relations and goodwill. • Creating a community of supporters. • Active communication with supporters. • Space for content publishing.
The main advantages of using advertisements on social media are as follows: the constant need for content creation can be profitable through the insertion of semantically related advertising; the monitoring is almost automatic; there is more flexibility in the advertising formats; with a limited investment, a great impact on customers can be achieved; cost per click is lower compared to other advertising formats; it is easier to segment and find the target audience; specific campaigns can be created depending on demographic and socio-demographic data (gender, age, interests or business experience) [58]. Research also shows that SNS have a positive impact on the profit and operation of enterprises, and the diversity of SNS utilisation plans are increasing [71,72]. Improvements of the company image or brand image, greater brand recognition, and better promotion of products and services have been detected [58]. Companies can use social media as a place where they can obtain information about their customers' needs and establish the relationship between the brand and customers at negligible costs [73,74]. Social media can be used to promote their brand´s image [75,76]. Social media is also recognised as a communication and public relations tool and, as such, it enables effective communications from brands and helps to develop relationships with the users. Social media interactions have a positive effect on the relationship between a user and a brand, which leads to greater credibility and loyalty [23].

Materials and Methods
We used a questionnaire to obtain data. Firstly, we conducted a pilot test in the form of an interview on a sample of 18 respondents, in order to improve the clarity and intelligibility of the questionnaire. Based on feedback from respondents, minor adjustments were made to the original version of the questionnaire. Respondents' answers from pilot testing were not included in our research. We then distributed the final version of the questionnaire from January to May 2020. The questionnaire was used both in printed and electronic versions. Initially, we preferred the printed version, because due to personal contact, the success rate of addressing respondents is significantly higher. On the other hand, due to COVID-19 restrictions in the Slovak Republic, the electronic form was often more suitable. We distributed the electronic form through social networks and shared contacts. We planned to examine the responses in terms of gender, therefore we used a stratified sampling method so that the distribution of respondents by gender roughly corresponded to the data for the whole Slovak Republic. Overall, we processed responses from 244 respondents, and their demographic characteristics are shown in Table 1.  Table 1 shows that the proportion of women in our research sample was 51.64%, which approximately corresponds to the proportion of women in the general Slovak Republic population. According to the data of the Statistical Office of the Slovak Republic, the proportion of women in the whole country in 2018 was at a level of 51.18% [68]. The second characteristic we were interested in was the respondents' age. We divided all respondents in two categories. The younger group consisted of respondents under the age of 40 (including 40), and the older group consisted of respondents over the age of 40, which was a proportion of 43.85%. According to the Statistical Office of the Slovak Republic, the average age of the population in the country is 40.82 [77]. Therefore, we used the limit of 40 years of age, when dividing the research sample in two parts according to age. In similar studies, it is common for authors to look at differences in gender and age. Therefore, we also focused on these indicators, because we assumed the possible existence of differences in the perception of advertising. There are more options for dividing consumers by age. However, we chose the structure of the questionnaire so that we could examine the younger and older generations. In line with the distribution of the population in the Slovak Republic, we chose the age of 40 as the limit.
The questionnaire was divided into four parts. There are many factors that can be used to examine impacts on consumers. We were interested in opinions on advertising oversaturation, the influence of advertising, annoyance by advertising, and credibility of advertising. In each of these four parts, we investigated opinions on 21 different types of advertising from the television to the internet formats. The answers to each question could be selected on a 3-point scale (never, seemly, absolutely). We chose an odd number of answer options in order to balance the positive and negative outcomes. At the beginning of the questionnaire, we found out the age and gender of the respondents, so that we could then evaluate the differences in these indicators. We considered the structure of the questionnaire compiled in this way to be meaningful, because similar research has been carried out in countries other than the Slovak Republic. We were most interested in the answers regarding social networks, but for comparison, we included questions for other forms of advertising in the structure of the questionnaire.
Firstly, we evaluated the responses using descriptive statistics. Next, we created a data matrix, assigning numbers to the scale of answers (never-1, seemly-2, absolutely-3) and then we calculated the arithmetic means of individual answers. However, the comparison of arithmetic means of the answers was not enough; it was necessary to determine whether the differences in the means were statistically significant.
All tests were calculated for a significance level of 0.05. This means that a p-value lower than 0.05 was considered to be the defined limit for assessing statistical significance. Our data were not metric but ordinal, therefore it was suitable to use non-parametric tests to determine statistical significance. In our study, we performed calculations for two types of comparisons. The first was the significance of the differences between the various types of advertising. In this case, we investigated the opinions of one and the same group of respondents (whole sample) in different situations. Therefore, we used the Wilcoxon signed-rank test for paired samples to compare the means.
The second type of comparison of responses was category-based evaluation. We were interested in significant differences in terms of gender and age. This case concerned constant independent samples (male and female, respondents up to 40 and over 40 years of age) we used the Mann-Whitney U test for independent samples to compare the means. The data analysis for the article was generated using the Real Statistics Resource Pack software (Release 6.8). Copyright (2013-2020) Charles Zaiontz [78].

Results
Firstly, we asked respondents what type of advertising oversaturation they perceived most. The answers to this question are shown in Table 2. The numbers of respondents and opinions are shown along with the corresponding percentages. The next column shows the average of the values for each question. The average was calculated from a data matrix, where numbers were assigned to the range of answers (never-1, seemly-2, absolutely-3) We used a similar procedure in the following tables for other questions. Table 2 shows that the greatest advertisement oversaturation was perceived by the respondents to be on television and on internet pop-up advertisements. On the contrary, they perceived the least advertisement oversaturation to be in the forms of advertising articles and leaflets promoting tourism services. The last two columns show the p-values of the Mann-Whitney test for two independent samples. They provide us with information on whether there was a significant difference in responses in terms of gender and age.
To verify whether there was a statistically significant difference in the calculated means, we used the Wilcoxon test for paired samples (Table 3). Descriptive statistics ( Table 2) show that the most overwhelming forms of advertising are pop-ups on the web and television. The significance of these differences is shown in Table 3. When we compared pop-ups on the web with other types of advertising, the calculated p-value was always lower than 0.05, with the exception of television. This meant that pop-ups on the web were significantly more overloaded with advertising than other types, with the exception of television. It was not clear which type of advertising was perceived to be the most oversaturated. When comparing TV and pop-ups on the web, the calculated p-value of 0.3895 is markedly higher than 0.05, which means the difference in means was not significant.
We were also interested in whether men and women answered this question in the same way or not. To determine whether the differences in the results were significant, we used the Mann-Whitney test for two independent samples. The biggest difference of opinion between men and women was discovered for the television and the radio, but the calculated p-values showed that the differences were not significant. It was similar in other cases. As Table 2 shows, a p-value higher than 0.05 was calculated for all advertisement types. This meant that the differences in responses were not significant. We can conclude that the question of advertisement oversaturation failed to show a significant statistical difference in the answers between men and women. In addition to gender, we also determined differences in responses in terms of age. We divided the whole sample into two parts. The first part consisted of younger respondents (under 40) and the second part of older respondents (over 40). Based on the descriptive statistics, we determined that the older generation perceived there to be more advertising oversaturation of all forms suggested, except for television. The Mann-Whitney test for two independent samples was used to test for differences. In all cases except television, a p-value of less than 0.05 was calculated. Therefore, we can say that the older generation perceived a higher advertisement oversaturation of all forms except television. People consider television advertising to be oversaturated, regardless of age. It is also confirmed by the fact, that this type of advertising had the second highest average in the responses of respondents. Television companies include advertising not only between individual television programs, but also during the broadcasting of news and films. This likely has a negative impact on consumer perception. However, for all types of internet advertising, there is a difference between the older and younger generations. Older people perceive most adverts as overloading (e.g., pop-ups on the web) more than younger people. The same is true for social networks and other types of online advertising. This is an expected finding. Younger people spend more time online and are therefore more used to advertising.   We also studied whether men and women have different views on the influence of different types of advertising. We noticed the biggest difference in the answers concerning advertising leaflets promoting food and cosmetics. Using the Mann-Whitney test for two independent samples, we calculated a p-value of 0.1077 (Table 4), which meant that no significant difference was confirmed. Similarly, for other types of advertising, the p-value was higher than 0.05. We did not find a significant statistical difference between men and women in the responses concerning the influence of each type of advertising.
When studying the responses in terms of age, we found remarkable data based on descriptive statistics. When we compared the average values of the answers, we found lower numbers for the older generation (over 40) for all types of advertising. This indicates that older people accredit less influence to advertising than younger people under the age of 40. We found the differences in means using the Mann-Whitney test for two independent samples. The calculated values were surprising and interesting. We tested all 21 types of advertisements, and the calculated p-values were lower than 0.05 for all of them. This means that statistically significant differences concerning the influence of advertisements were found for each type of advertising in terms of age. People over the age of 40 generally admit a lower influence of each type of advertising than younger people under the age of 40. We expected this result, especially concerning social networks and other modern forms of advertising, because among the older generation, distrust in newer forms may prevail. On the other hand, we only found out the opinions of the respondents and not the real impact, which could be different. However, this was not the subject of this article.   Table 6 shows the answers to the question about annoyance by advertisement for each advertisement type. The descriptive statistics indicate that people are most bothered by television advertising. The answers should be partly related to opinions on advertising overload. For this question, television was one of the two worst-rated forms of advertising; the average rating was 2.57. The respondents' opinions of TV advert annoyance were slightly worse, with an average rating of 2.58. This is perhaps a bit surprising, because if an advertisement on TV bothers the viewer, it is possible to partially avoid it by skipping to the next part of the broadcast. However, many customers in Slovakia probably do not have such a service and, moreover, it is not always available; for example, if the programme is watched live. The form of advertising with the highest overload was pop-ups on the web, with a value of 2.61. However, in annoyance, the rating was lower, at only 2.45. We can explain this by the fact that although consumers perceive a lot of advertising on pop-ups on the web, it does not bother them so much, because they can get rid of it and close the advertising window. However, in the case of television, the advert is inescapable, and in addition, advertising is often very long-lasting.
To verify whether there was a statistically significant difference in the calculated means, we used the Wilcoxon test (Table 7). When we compared TV advertising and other types of advertising, the only case where the p-value was larger than 0.05 was e-mail advertising. The calculated p-value was 0.1203. This meant that the difference between annoyance by television advertising and e-mail advertising was not significant. However, when we compared a TV advertisement with another type of advertisement, the p-value was always lower than 0.05, which meant that the differences were significant. Therefore, we can say that television advertising bothers respondents the most, with the exception of e-mail advertising.
We also conducted a survey on the differences between men's and women's opinions on annoyance by various types of advertising. The biggest difference in the answers was observed for the electrical appliance leaflets. Using the Mann-Whitney test for two independent samples, we calculated a p-value of 0.0842 (Table 6), which meant that no significant difference was found. Similarly, for other types of advertising, the p-value was higher than 0.05. We did not determine a significant statistical difference between men and women in the answers about annoyance by various types of advertising.
Additionally, in this issue we investigated the differences in terms of age. Here again, we discovered an interesting fact based on descriptive statistics. In all questions, the mean was higher among the older generation, which indicates that older people are annoyed by advertisements more than the younger ones. Determined differences in means were tested using the Mann-Whitney test for two independent samples. The calculated values were surprising and very interesting again. We tested all 21 advertisement types, and a p-value lower than 0.05 was calculated for each of them. This means the statistically significant differences in terms of age were determined for every type of advertisement concerning the question of annoyance by advertisement. This suggests that people over the age of 40 are generally bothered by advertising more than people under the age of 40. We already expected this result with regard to the evaluation of previous questions. Again, there were differences between the perception of advertising by the older and younger generations. At the beginning of the research, however, we did not expect such clear conclusions.  Table 8 shows the answers to the question about the credibility of advertising. The descriptive statistics indicate that the radio and blogs on the web have the highest credibility. When we determined the difference between the most reliable types of advertising, the calculated p-value of 0.9389 (Table 9) was much higher than 0.05, which meant that the difference between the credibility of advertising on the radio and blogs on the web was not significant. Significant differences were determined only between the advertisements with the highest and the lowest credibility. For example, the calculated p-value for the comparison between radio advertisements and pop-ups on the web was 0.0013. LED panels were no longer in last place in the evaluation, as was the case in terms of impact factor. In the case of credibility, LED panels were rated higher than 11 other forms of advertising.
No significant difference between men's and women's answers about the advertisement credibility was determined concerning the gender (Table 8).
Concerning the age, significant differences were found in the case of two types of advertisementthe television and medicament leaflets. Both types of advertising were considered more reliable by the younger generation than by the older generation.

Discussion and Conclusions
Companies are pushed to include sustainability in their strategies in order to respond to growing pressure from stakeholders and to protect their market shares [79]. Corporate sustainability aims to change organisations into responsible enterprises that pay attention to economic, environmental, and social aspects of their operations, in order to meet current societal needs without jeopardising the requirements of future generations [80]. Accordingly, sustainability, becomes imperative because it provides companies with a view to access to further projects and financial sources in the future, and supports competitiveness in the contemporary marketplace.
The dynamic development of the environment in all spheres also forms the area of marketing communication. Developing trust in a product, brand or company is a significant part of building a successful consumer-company relationship. Advertising as a communication tool that elicits lots of attention and emotions is a big part of the trust-building process and influences the receptiveness of the message. Companies undertake various efforts to make their messages more attractive to recipients and seek new ways of attracting customers' attention [54]. Authors Poornima, Saumya and Umesh [34] suggest that, due to the number of internet users worldwide rapidly increasing, along with its use by all age groups and all types of people, the internet has become one of the major communication mediums and most contemporary companies and organisations rely on digital advertising and marketing techniques to improve their overall sales and revenue. Online marketing has proven to be effective and efficient so far when compared to other forms of advertising and marketing.
If companies want to be competitive, they should choose a combination of marketing communication activities to promote their products in order to attract the widest possible range of potential customers. The current customer is demanding, and competition in every area of sales is great, which means that everything depends on the attractiveness of the promotion of the companies. This means, how well can they "sell" their products or services. Contemporary consumers need information anywhere and anytime. Customers buy and view products or services at all times. They want to have their questions answered immediately. This is why the importance of internet advertising, and especially advertising on social networks, is increasing. It is necessary to provide customer support 24/7. If a company wants to be competitive and successful, it must be discoverable for new customers. The social networks are the right tools for this.
Many companies use social media as a main advertising strategy. This is the case of mobile operators, for example [58]. One of the advantages of social media is their support of new patterns of behaviour of customers based on sharing the advertisements. This supports the sustainability of the companies in the market. Social media is changing peoples' traditional behaviour patterns. People are increasingly using social media to search for information instead of other resources such as television, magazines, and the radio. Therefore, companies need to create effective online advertising strategies because the internet is now the best platform to reach the largest number of consumers [34].
In this article, we dealt with the attitude of customers in Slovakia to various forms of advertising. In order to obtain an overall picture of customers' perception of advertising, we included not only more modern forms of advertising, for example advertising on social networks, but also more traditional forms of advertising used by companies in Slovakia, such as television, radio, leaflets, etc. We focused our research on several areas. We determined which forms of advertisement respondents perceived to be most oversaturated, which forms of advertising respondents considered the most reliable, by which forms of advertising respondents are annoyed most, and which have the greatest influence on them. In each of these areas, we investigation whether there was a difference in the perception of different types of advertisements in terms of gender and the age of respondents.
We assumed (as stated in the study by authors Poornima, Saumya and Umesh [34]) that advertising on social networks would have a relatively large influence on respondents compared to other types of advertising, which was confirmed. Apart from leaflets for clothing, footwear, food and cosmetics, respondents considered advertising on social networks to be the most influential of all advertisement forms included in the survey. This observation is contrary to the statement of authors Pikas, Sorentino and Hung, Li, Tse [32,33], according to whom the advertising on social networks is perceived worse by customers and is considered less persuasive compared to traditional forms of advertisement. We consider this to be positive, because advertising on social networks requires relatively lower costs compared to many other forms of advertising. At the same time, it can be targeted at suitable customers, which is why a greater efficiency of advertising costs can be expected. Another advantage is that it enables communication with customers 24 h a day throughout the year, and information, content and style can quickly be changed. Advertising in social media can be considered a direct communication tool conducive to the promotion of sustainable development [81]. At the same time, we also determined older people to be less influenced by advertising than younger people (under the age of 40) concerning all included forms of advertisement. In the case of social networks, we assumed the opposite result because social networks are used more by younger people in Slovakia [6] and they also spend more time on social networks on average [7]. At the same time, we investigated advertisement oversaturation on social networks for more than half of the respondents (54.10%), but respondents considered the television and the internet (in the form of pop-ups) to be the most oversaturated by advertisements. It is interesting that the older generation (over 40) perceived advertisement oversaturation of all forms of advertising, more than the younger generation, except on television. The extent to which the form of advertising bothers respondents and at the same time the extent to which consumers trust it may ultimately determine the efficiency of the advertising costs. In connection with the extent to which the type of advertising bothers respondents, we found the more traditional forms of advertising, specifically on television, to be the most annoying for the respondents, along with e-mail advertising. This is probably due to the fact that respondents come into contact with these forms of advertising most often. At the same time, older people are more annoyed by advertisements than younger people. However, according to authors Miklošík, Starchon, Vokounová, Korcoková [40] the younger generation considers TV advertisements to be more annoying, which is why they tend to avoid the medium. Advertisements on television are considered to be a costly form of promotion, with the disadvantage of one-way interaction with the customer. The advantage of the radio advertisement is, that the customers change the radio station during the advertising spot to a small extent, which means that the advertised product or brand can enter the consciousness of the customers relatively fast. The advantage of the outdoor advertisement is the fast reaching of customers´consciousness through multiple repetitions. Regarding the credibility of individual advertisements, we found that respondents considered the advertisements on the radio and various blogs on the web to be the most reliable. In terms of age, we found significant differences only in the case of two types of advertising, namely the television and leaflets promoting medicaments. We found that these types of advertising are considered more reliable by the younger generation of respondents (under the age of 40) than by the older generation. We did not find a significant difference between the answers of men and women in any of the areas of interest (opinions on advertising oversaturation, the influence of advertising, annoyance by advertising, and the credibility of advertising).
It is important to mention that considering users' perceptions can help managers to develop more accurate business strategies [82]. Any business owner knows that advertising is a gateway to increased income [83]. However, depending on the target group for which the product is intended, it is necessary to use the correct form or combination of forms of advertising. It can support the sustainability of the company in the market with regard to financial sustainability at the same time.
In particular, customer engagement objectives, budgetary availability, product characteristics and the target market profile are the main considerations when choosing the most effective corporate sustainability strategy [11]. Regardless of a company´s focus, the communication strategy should be based on up-to-date environmental and social topics, which includes sustainability of the products and not only the sustainability of the company in the market.
The capability of the company to integrate the sustainability strategy into the role of the company and the relationships with all the parties involved could be decisive about the success or fail of the company in the 21st century [84]. Sustainability should therefore become a central component of all marketing thinking and practice [85].
The summary of observations includes the attitudes, opinions, and mutual differences of the group of respondents to advertising. The various effects and subsequent influence of advertising has been known since the creation of the first advertisements. Advertisements were created to provide information, but over the time they became a tool to indirectly influence decisions. The use of different techniques in advertising can affect everyone differently, whether positive or negative.
It should considered that our sample of respondents found that although advertising on social networks affects them to a great extent, they perceived a lot of advertising oversaturation on social networks as well. At the same time, it was not one of the forms that consumers would trust the most, nor it was one of the forms that bothered them the most. Our findings do not mean that it is necessary to completely change the traditional form of providing advertising information to the customers, e.g., radio advertisements trusted by customers or leaflets (e.g., advertising food, cosmetics, clothing, shoes) influencing customers to a relatively great extent. The goal is to consider including more modern forms of advertisement in the promotion; blogs were considered to be more reliable advertising forms by the customers, and social networks enable more interaction and both-way communication with the customers which fosters closer relationships.
Companies have to realise that one of the most important criterion for employing their advertising strategies effectively is the knowledge of the customer target groups to whom they offer their products.
The results of the research presented may help companies to focus on the choice of a suitable form of advertising and a specific medium, considering the specific product and target group of customers in the future.
One of the possible directions in the future is to expand the research and increase the number of respondents as well as to determine which social networks are used by companies in more detail and if the companies use them as information channels or also to stimulate communication. In our article, we analysed the perception of advertising by customers. Only the customer opinions were analysed, therefore the real influence of the advertising may not be reflected, which may be the subject to further research. At the same time, it would be interesting to deal with measuring the effectiveness of advertising-eye-tracking, for example. In the future, we plan to pay more attention to the psychology of visual perception in advertising.