 Large companies such as Saudi Aramco run their own bus transport operations, connecting residential and industrial camps of the company with Dhahran, Dammam, and Khobar.Many smaller residential compounds also operate their own bus services which are typically used for transport to places of work or shopping trips by residents.Mobile telephone communications are provided mainly by STC, Mobily and Zain, which have launched 3G and 4G services to their customers.