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; wireless entertainment-related contents and services primarily through content-specific portal sites; wireless finance-related contents and m-commerce services; and wireless news and search services comprising news content access, dictionary resources, and weather information 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 calling 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 satellite digital media broadcasting; telematics; 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 of December 31, 2011, the company had approximately 26.5 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.