The field of electronics comprises the study and use of systems that operate by controlling the flow of electrons ( or other charge carriers ) in devices such as thermionic valves and semiconductors. The study of new semiconductor devices and surrounding technology is sometimes considered a branch of physics. This article focuses on engineering aspects of electronics. The design and construction of electronic circuits to solve practical problems is an integral technique in the field of electronics engineering and is equally important in hardware design for computer engineering. All applications of electronics involve the transmission of either information or power. Most deal only with information. The different type of Electronic equipments that has invaded our offices and homes these days is also mind boggling. Many things we use at home and office are “remote controlled”, for example, Television (TV), Air-Conditioners, Audio equipment, Telephone, etc. It is almost close to “magic” how even a child, now-a-days, can switch channels, or increase decrease the volume of sound in a TV at home by just clicking on a few buttons.