Chad, officially known as the Republic of Chad, is a landlocked country in north-central Africa. It is bordered by Libya to the north, Sudan to the east, the Central African Republic to the south, Cameroon to the south-west, Nigeria to the southwest (at Lake Chad), and Niger to the west. Lake Chad, after which the country is named, is the largest wetland in Chad and the second-largest in Africa. The capital N'Djamena is the largest city. Chad's official languages are Arabic and French. Chad is home to over 200 different ethnic and linguistic groups. The most popular religion of Chad is Islam (at 55%), followed by Christianity (at 40%). Chad remains plagued by political violence and recurrent attempted coups d'état. Chad is one of the poorest and most corrupt countries in the world; most inhabitants live in poverty as subsistence herders and farmers.