They say a picture is worth a thousand words. Following that line of thinking, I suppose GIFs are worth a couple thousand words at least, because it isn't just made up of a single picture. In fact, it's basically a short clip converted into GIF format. You've probably seen a lot of these, going around on the web, especially after huge events like the Golden Globes.
They're not hard to make, although you'll need at least some skill to create such images. If you've ever wanted to tack on your face in existing GIFs, then you're in luck because you can do so with the GIF Yourself app.
Simply fire it up, choose an existing GIF, take a selfie (or choose from an existing picture of yourself), and tap to generate the GIF!