Instantly resorted to name calling, and claiming I'm a "troll". Children these days are quite rude. Anyway, your original post was;
Asking your question, and then supplying the model number will lead anyone to assume you're asking what that is, not what the sole purpose of it's function is. What I gave you is a link explaining EXACTLY what it is, and what the common uses for it are. My original statement still stands, in that you could have simply googled it for your answer. Sure, this is a discussion board, but if you've already "Gone through the articles" which all state the same exact uses, you should already have your answer. If Tech sites dedicated to the Xbox and PlayStation aren't sure what it's for, what makes you think the average joe is going to know?