Tanzania Mainland lies between 10 and 120 south of equator and between 290 and 410 east of the Greenwich Meridian. It shares a border with Kenya and Uganda to the north and Mozambique, Malawi and Zambia to the south. To the east lies the Indian Ocean while Rwanda, Burundi, and the Democratic Republic of Congo are to the west. Tanzania has a landmass of 881,000 square kilometres and a population of 39.5 million people. The population consists of people from about 120 different tribes, each with its own language. However Kiswahili is spoken by all tribes and is the national language as well as the main language of official communication while English is the second official language. Kiswahili is the medium of instruction in primary schools while English is used as the medium of instruction in secondary schools and in post-secondary education. Christianity and Islam are the main religions practised by more than 90 percent of the population, but each has many different sects. Tanzania was a British protectorate for 42 years, that is, from 1918 to 1960 before it became independent in 1961. It is a multiparty state and enjoys strong friendship and cooperation with its neighbours mainly through its membership to the East African Community (EAC) and the Southern Africa Development Community (SADC).