Music games have always been around but they all boil down to time button commands. They have gotten so prevalent that it was definitely time for a change. There have been karaoke games which requires you to sing, but the most popular today are the guitar controllers used in the GuitarFreaks and Guitar Hero franchises. The Guitar Hero controller has 5 color coded buttons and a strum bar which can make you feel like a guitarist. There has always been drum mania in the arcades which requires actual skill to play, but the most commercial on home consoles is Harmonix's Rock Band Drum set. It has four pads and a bass pedal which in conclusion can actually teach you the basics on drumming. Recently, DJ Hero has included some larger peripherals, mimicking a full turntable. Recently, guitar controllers have been evolving, with PowerGig: Rise of the SixString and Rock Band 3 including more realistic guitar controllers with appropriate string and finger placement.
Musical peripherals connect to your gaming console in different ways. Earlier guitars, like the one that came with the first Guitar Hero, were wired and connected to your USB port. As the peripherals got better, they became wireless. Now all you have to do is connect a dongle to your USB port. Because their were more peripherals than USB ports, dongles come with USB ports attached to them. Microphones for Rock Band And Guitar Hero are wired. Microphones for karaoke games like Lips and Singstar are wireless. Singstar microphones used to be wired and come with a hub that would connect to your USB port. The hub let you connect two microphones. Guitar Hero on the DS has a peripheral that connects to the GBA port so you can play the notes that appear on screen.
Some people find this preponderance of musical peripherals to be extreme, as it fills up some players living rooms. However, some enjoy the many options out there.