ManKier

The most complete and up-to-date collection of online man pages.

New! 3rd anniversary blog post: From troff to HTML5 (2016-09-27).

Search/Explain

Common Commands

ls, cat, grep, rsync, bash, less, htop, ssh...

Explain a Command

Delete files extracted from a tarball
tar -tf file.tar.gz | xargs rm -r

Generate a random 16-char password
strings /dev/urandom | grep -o '[[:alnum:]]' | head -n 16 | tr -d '\n'

Print the largest files or folders in the current dir (including ones starting with a dot)
du -s * .[^.]* | sort -n | tail

Those are just a few examples - it's a quick way to see what commands and their options do before running them.