What is unit testing

Unit testing refers to checking and verifying the smallest testable unit of software.

For unit testing in the meaning of the unit, in general, according to the actual situation to determine its specific meaning, such as C language unit refers to a function, Java unit refers to a class, graphical software can refer to a window or a menu. In general, the unit is the smallest man-made provisions of the function module being measured.

Unit testing is the lowest level of testing activity to be performed during the software development process, where individual units of software are tested in isolation from the rest of the program.