1.date command
date command prints the current date time.
$ DATE
2.cal command
cal command is used to display a calendar in your shell.
$ CAL
3.whoami command
whoami command is used for which user account you are using in this system.
$ WHOAMI
4.pwd command
pwd command is used to find out the absolute path of the current directory.
$ PWD
5.cd command
cd command is used to change your current directory.
$ CD