If you're new to iPhone, iPod touch, or iPad and are wondering just what exactly Bluetooth is and what it means to you, worry not -- iMore has you covered. Bluetooth is an open standard wireless communications protocol, which just means that it's a commonly available way for devices to talk to each other, and to other electronics, without having to be plugged in together. The most common things iPhone, iPod touch, and iPad users do with Bluetooth include connecting to headsets and speakers.
Bluetooth works over short-wave radio (between 2400 and 2480 MHz if you're techie) and has a range of about 30 feet. If you move further away than that, say leave your iPhone in your car and go into a store, you'll lose connection.
There are several different Bluetooth profiles, each of which enables its own type of functionality. iOS doesn't support all Bluetooth profiles, but it does support several important ones.
Most previous iOS devices, including iPhone, iPad, and iPod touch support up to Bluetooth 2.1 + EDR (enhanced data rate). EDR allows for faster data transfers, meaning smoother, better sound support and internet speeds (between 2 and 3mbps).
Bluetooth 4.0, a newer specification is supported by the iPhone 4S and will presumably be supported by future devices like the iPad 3. Bluetooth 4.0 allows for BHS (Bluetooth high speed) and BLE (Bluetooth low energy), which aim to provide better, faster data with lower battery drain.
There are very few Bluetooth 4.0 accessories available yet, for example the Find My Car Smarter. However, Bluetooth 4.0 offers the potential for more ubiquitous, persistent, and useful peripherals than ever before.