Installation (or setup) of a computer program (including device drivers and plugins), is the act of making the program ready for execution. Because the process varies for each program and each computer, programs (including operating systems) often come with an installer, a specialized program responsible for doing whatever is needed for their installation. Installation may be part of a larger software deployment process.
Installation typically involves code being copied/generated from the installation files to new files on the local computer for easier access by the operating system. Because code is generally copied/generated in multiple locations, uninstallation usually involves more than just erasing the program folder. For example, registry files and other system code may need to be modified or deleted for a complete uninstallation.