Electronics is a sub branch of physics which includes the study of electrons, flow of electrons in various devices like diode, resistance, capacitance etc. This flow of electrons is also known as charge. So the term 'electronics' involves all the study of flow of charge, various functions of the devices which use charge, machines which use electronic components and every thing which use electrons/charge for their working.

Electronics can be further categorized as:

Many other types of electronics also exist.

History

Story of electronics starts from 1880, It was Thomas Alva Edison who observed the flow of current between two elements in an evacuated glass tube while performing an experiment. This was the first step of the electronics era. After Edison's experiment, a lot of other successful experiments were done by many other scientists including John A. Fleming and Lee de Forest (1907).

In 1947 when transistor was invented by Bell labs, it was the milestone in the journey of electronics. After the invention of transistor it became possible to integrate various electronic components on the circuit. Now since the size of circuit was reduced, a new branch of electronics was created and this new branch was known as 'microelectronics'.
 

There is not a very large variety in compressor designs. The following are the main types of compressors which are commonly used: