How to list installed packages in command line?

[kooldino]

I know there's a way to do it, but I can't recall.

I thought it was an apt-get option...basically it would list all of the installed packages in the command line.

[lykwydchykyn]

dpkg --get-selections

[kooldino]

Thank you! I was thinking it may have been a dpkg option, but I second guessed myself.