When I install packages and development libraries, I often only need them for a short amount of time.

When I am done with something I've installed with apt-get, or installed from source, or installed through any other medium, I want to get rid of it.

I loathe the idea that I have to periodically reinstall my OS because I don't know how to keep track of things I've added and undo changes. This also goes for editing configuration files.

Is there some way to keep track of all kinds of installations? And secondly, is there a way to keep track of changes to non-home files so that they can be safely undone?

I'm not using Linux at the moment, but I'd like to make the switch. This might be something that convinces me if it's possible.