Why are some downloads of the same program different sizes?

[Crazy Mother Trucker]

Say, for instance, that I wanted to download a program like Adobe Illustrator. There are several options, ranging from 20MB to 100MB. What's the difference? Should I go for the larger one?

Thanks,
Tyvek

 

[Mary W]

One of them might be crap, or both. Or they both include virii/trojans. Try 'em out.