When it comes to how well you perform while playing a game, nothing is more critical than the controller you're using. PC gamers use keyboards and mice, but console players use the traditional controller. This handy little accessory has always been great for platformers and action games, but it's been perceived to be weaker for RTS and shooter games.
Microsoft broke this gaming barrier years ago with their original Xbox, which used a controller that players found intuitive and easy for playing games like the blockbuster Halo, the start of one of the most popular shooter games of all time. Microsoft further improved upon their design with the Xbox 360 controller.
Wireless Speed
The original Xbox controller was wireless, and players had limited (relatively) freedom, being forced to stick near their console and facing someone tripping over the cords. On the other hand, the Xbox 360 controller is available as a standard wireless model, giving players the freedom to move around and quickly switch controllers between players.
The only downside is that the controller uses batteries instead of supplying power through the cord, and so the controllers won't last forever without a recharge. However, the batteries last quite some time without needing to be replaced. Under such circumstances, most people prefer the wireless Xbox 360 controller.
However, you can always opt to get the wired version for yourself. This way, you'll never need to recharge or replace the batteries, and you have an instant connection between the the controller and the console. While wireless advancements in recent years have made the connection less prone to interference and faster overall, you may want to go with the wired controller if you absolutely require that your actions are instantly responsive on screen to react with unparalleled speed.
However, the wireless Xbox 360 controller is reportedly nearly as good by pro and casual gamers alike. Another great reason to pick up a wireless Xbox 360 controller is to not get confused by the tangle of wires when your friends come over. This makes keeping track of who has which controller (such as player one, two, etc.) much easier because there won't be a mess of wires confusing you.
Also, many people with large screens or projectors prefer the wireless controllers because they can sit further back at the optimum viewing distance from their screen, making the games all the more enjoyable. Depending on your play style, you'll want to choose which Xbox 360 controller is right for you.