When you're starting out in photography, with your shiny new DSLR, the world of lenses can be complex and scary place: prime this, wide angle that, and what the hell is focal length anyway? Don't worry! This video should have you covered.
If you can get over the fact that it's sponsored by Pentax -- so, surprise, only Pentax lenses feature -- then it actually serves as a great introduction to what various lenses can be used for. If you're a newbie, prepare to learn something -- and spend some money. [YouTube]