tarball?? huh?

Whenever I dowload a new Open Source application, I get the option to get the i86 installer edition, (either .exe or .zip) but there are options there to get the tarball, or the .tar or .gz files. I don't know eough to install these files, but I'd like to know enough. I think I would need to have the appropriate code compilers to make it work. Maybe if I throw this thought out into the ether I will find a answer.