Category OS

tee command

less command on the picture is used to display information to the terminal one page at a time. less is faster than other command because it ...

File permission

If you type ls -l, you can see file permission like below. First letter indicates if it is a Directory. Next each group of three characters ...

Pipe & Redirection

Pipe is used to pass output to another Program or Utility. thing1 | thing2 thing1’s output s will be passed to things2 Program or Utility. ...