An OS is a collection of system program that together controls the operations of computer system. Example:UNIX, MS-DOS, MS-Windows, Linux etc.
This note contains brief description on the Operating System.
The booting is a process of loading system files into working memory (RAM) to become ready to work. There are two types of booting: cold booting and warm booting. This note contains short description on booting , file directory and DOS commands.
Internal command are built in the COMMAND.COM files. It can be executed from any DOS prompt because each of the internal commands are memory resident. Some of the examples of internal commands are: DIR, CLS, COPY etc.
This note contains further description on internal commands used in DOS.
Commands that need external additional file with command.com are external commands. Example: XCOPY, CHKDSK, LABEL, TREE etc. This note contains brief description on external command used in DOS.