If you get a skinned version of Android with your phone, the chances are high that it will have its own take on the Android keyboard. Some of these are great, and some… less so. Google has just removed that problem at a stroke by making the stock Android 4.2.2 keyboard available as its own download.
There are some devices where having a different keyboard makes sense, especially depending on screen size, but I've often found manufacturer-supplied keyboard layouts to be annoying. Google's Keyboard is simple, it works, and it's free. The only downside -- and it's quite explicit about this when you install it -- is that like much of Google's output, it's a data-hungry little creature that captures each keystroke for Google's own purposes.