Before I edited the title to fit the actual question, it stated, why do we need iTunes? That tells me that you know what iTunes is, however, in the post itself you claim to not know what they are. Still, you found your way to an Apple-centric forum, figured out how to post in the Ask a Question section that can only be accessed via the Internet, yet, you couldn't use the same Internet to find information in regard to Apple IDs and iTunes. I'm not buying it.