Its a mobile broadband internet provider company.
Basically, it allows you to connect to the internet via radio or cellphone towers, so you can connect to the internet on the go without needing to be tied down to cables or wifi hotspots.
Such technology as been increasing popular with smartphone that allow them to be internet enabled as well as many laptop users on the go. Although mobile broadband is generally more expensive and slower then Cable/DSL/Fiber-based internet providers. However, you can still be online while driving in a car (as long u are in range of a tower ofcourse)