SK Telecom Co., Ltd. provides wireless telecommunications services principally in Korea. The company offers cellular voice services, including wireless voice transmission and related value-added services; wireless global roaming services; and interconnection services to connect its networks to fixed-line and other wireless networks. It also provides wireless data transmission services, such as wireless Internet access services, which allow subscribers to access online digital contents and services, as well as to send and receive text and multimedia messages; and wireless entertainment-related contents and services primarily through content-specific portal sites; and wireless finance-related contents and m-commerce services. In addition, the company offers broadband Internet and fixed-line telephone services, such as video-on-demand and Internet protocol television services; and local, domestic, and international long-distance fixed-line telephone services to residential and commercial subscribers. Further, it provides international telecommunications services, such as direct-dial; pre and post paid card calling services; bundled services for corporate customers; voice services using Internet protocol; Web-to-phone services; and data services. Additionally, the company offers social networking services; mobile in-app advertising services; and fixed-line and online community portal services. It also operates 11th Street, an online shopping mall; and T Store, an online open marketplace for mobile applications, as well as telematics service. As of December 31, 2012, the company had approximately 27 million wireless subscribers. The company was formerly known as Korea Mobile Telecommunications Co., Ltd. and changed its name to SK Telecom Co., Ltd. in March 1997. SK Telecom Co., Ltd. was founded in 1984 and is headquartered in Seoul, South Korea.