With all these "Vines" popping up all over the place, I still haven't figured out what it is. Is it like a Video Tweet or something? Any help clarifying what it is will be appreciated.

From what I understand they're 7 second videos that are completely random. I've seen some pretty good ones. I'll admit I've spent hours watching compilations.

When it came out it was basically instagram but in video form. You make a 7 second video of anything and then post it.

Some of them are hilarious. I've seen one where this guy points his comb as a gun and aimed it at a couple of students.

Okay, it doesn't sound as funny when you type it...

It's like Twitter but less useful and more obnoxious.