Bluejacking involves sending unsolicited messages to Bluetooth-enabled devices within a 10-100 meter range. It originated when a man named Ajack used his phone to send another phone a message saying "Buy Ericsson!" as a prank. To bluejack, one enables Bluetooth on their device and then uses software to send messages or contact cards to nearby discoverable devices without pairing. While mainly used to interact with strangers, it could also be used to revolutionize marketing by sending advertisements and product information to Bluetooth phones of people nearby.