Bonjour is one of the programs that come bundled with nearly every piece of Apple software (most notably iTunes) that handles a lot of its automatic discovery techniques. Best described as a hybrid of IPX and DNS, Bonjour discovers broadcasting objects on the network by using mDNS (multicast DNS) with little to no configuration required. Many admins will deliberately disable this service in a corporate environment due to potential security issues, however in a home environment it can be left up to the user to decide if the risk is worth the convenience.