The problem with one program to do mulitple task include: 1. It would be a lot more expensive. 2. It would be a lot bigger 3. It would be even more prone to errors and crashes. Not everyone wants the same thing. It's better to have a bunch of little programs that do only certain things so that the people that are interested can use them and the people that aren't don't have to tie up their machine with something they don't want.