Touch
creates a blank files

cat
Prints files to input, or reads and returns input.

chown
Changes ownership of files and directories

date
Displays or sets the current date and time.

diff
Shows differences between files.

exit
Ends a process, and returns to the parent process.

find
Searches for files.

finger
Looks up user information.

grep
Look for lines which match a given string or regular expression.

head
Prints the first few lines of a file.

kill
Terminates a process by PID.

less
Displays the content of a file.

lprm
Removes printer queue requests.

man
Displays the manual page for a program.

more
Prints the contents of files.

passwd
Creates or changes passwords.

ps
Gives a list of all active processes, along with other information.

rlogin
Logs into remote systems

su
Logs in as another user.

tail
Prints the last few lines of a file.

telnet
Communicates with other hosts via the telnet protocol.

who
Gives a list of logged in users.