How do you un-install software?

[gradnite]

Hi.

I want to un-install Mozilla for example, so that I can just have Firefox on the system. How do you un-install applications?

Thanks.

[user unknown]

If you installed it with apt, you can uninstall with

apt-get remove mozilla

I guess

[gradnite]

I need a tutorial on using apt. Any suggestions on where I can find such a thing? The above did nto remove mozilla.