I got my first gaming keyboard after I started getting into the game Starcraft. I initially just used the mouse and a few keyboard shortcuts. But as I got more and more into the game and started playing a higher caliber of player I realized that I needed to get quicker. That is when I saw a video of some Korean gamers who used customized gaming keyboards. Watching them manipulate the keys was like watching a master piano player, it was incredible how fast their fingers moved.
After that I went down to my local game store and talked with the guy behind the counter for probably 30 minutes about gaming keyboards. He recommended a basic model that they had in the store for starters (These can get as complicated and expensive as you want them to be) and I started using it that night.
It took a while to get the hang of, but once I did my skill in the game shot through the roof. I was playing on a level that I didn't think was possible. Now I use it for all the games I play and I have transitioned from a skilled gamer to an elite gamer. And it is all because of this new piece of hardware.