If you're new to iPhone, iPod touch, or iPad and are wondering just what exactly AirPlay is and what it means to you, worry not -- iMore has you covered. AirPlay is Apple's term for their audio and video streaming technology. It's what lets your iOS 5 device, or iTunes on Mac or Windows, beam videos over Wi-Fi to your Apple TV so you can watch movies and play games on your big screen TV, or music to your AirPort Express router, so you can listen on your higher quality speakers.
AirPlay Mirroring is a more recent addition to iOS that works with iPad 2 or iPhone 4S and lets you not only beam music or video, but entire iPhone or iPad apps. Anything from Facebook to your favorite crosswords, racing, or fighting game can be sent via Apple TV to your HDTV, with your iPhone, iPod touch, or iPad remaining active as the controller. Some games, like [Real Racing 2](http://www.imore.com/tag/real-racing 2) even let you participate in multiplayer games using AirPlay, with each person using their own device to control their own car, all displayed together on the big screen TV.
AirPlay is proprietary and not an open standard, which means Apple gets to control who uses it. Several other companies have licensed AirPlay, however, and you can find a growing range of AirPlay-compatible audio equipment. There's also some software out there that can run on your computer and tie into AirPlay, like BananaTV that lets you beam to your Mac instead of a TV.
Your iPhone, iPod touch, iPad, or computer running iTunes needs to be on the same Wi-Fi network as your Apple TV, Airport Express, or other hardware for AirPlay to work, but because Wi-Fi has high bandwidth it usually makes for a solid, stable connection. It's real time. It's encrypted. And most of the time, it "just works"