why is it an .rar and not .exe?

[skinnyman9000]

Hi, just rented out Rise of nations today and want to crack it. Now ive used this site before and whenever i download a game fix it is always .exe, an executable file. But this time i went to get the 1.03Version game fix and it was something something .rar. Firstly, why has it changed, and secondly what are .rar files, cus my comp tries to read them as a web page.

Cheers for any help
Chris