How to effectively work with multiple files in Vim

I've started using Vim to develop Perl scripts and am starting to find it very powerful. One thing I like is to be able to open multiple files at once with: vi main.pl maintenance.pl and then hop between them with: :n :prev and see which file are open with: :args And to add a file, I can say: :n test.pl which I expect would then be added to my list of files, but instead it wipes out my current fil