Today, the self-assembled monolayer (SAM) approach for surface functionalization is regarded as highly versatile and compelling, especially in the immobilization of biomolecules and fabrication of novel supramolecular architectures. Most of the scientific articles recently published on biosensors use the concept of SAM to generate different surface functional groups for the immobilization of biomolecules such as antibodies, proteins, and enzymes. Due to the simplicity of the formation process and lack of requirement for costly instruments, this approach is prominent among researchers working in the field of surface functionalization and biosensing devices. Herein, we have reviewed a wide range of literature reports on electronic devices such as chemical sensors, biosensors and organic film transistors that use SAM concept for their purposes. In this review article, effort has been made to provide information about the SAM functionalization procedure, i.e. the technique used, the molarity of the SAM solution, and other physical/chemical conditions involved. Moreover, the fundamental concept of the monolayer, the types of monolayers on air/water interfaces, the techniques used for SAM formation on solid substrates and the use of SAMs for patterning are discussed.