Chad, officially known as the Republic of Chad, is a landlocked country in central Africa. It is bordered by Libya to the north, Sudan to the east, the Central African Republic to the south, Cameroon and Nigeria to the southwest, and Niger to the west. Due to its distance from the sea and its largely desert climate, the country is sometimes referred to as the "Dead Heart of Africa".

Chad is divided into three major geographical regions: a desert zone in the north, an arid Sahelian belt in the centre and a more fertile Sudanese savanna zone in the south. Lake Chad, after which the country is named, is the largest wetland in Chad and the second largest in Africa. Chad's highest peak is the Emi Koussi in the Sahara, and N'Djamena,(formerly Fort-Lamy), the capital, is the largest city. Chad is home to over 200 different ethnic and linguistic groups. Arabic and French are the official languages. 

Each year a tropical weather system known as the intertropical front crosses Chad from south to north, bringing a wet season that lasts from May to October in the south, and from June to September in the Sahel.Variations in local rainfall create three major geographical zones. The Sahara lies in the country's northern third. Yearly precipitations there are under 50 millimetres (2 in); in fact, Borkou in Chad is the most arid area of the Sahara. Vegetation throughout this belt is scarce; only the occasional spontaneous palm grove survives, the only ones to do so south of the Tropic of Cancer. The Sahara gives way to a Sahelian belt in Chad's centre; precipitation there varies from 300 mm to 600 mm (12–24 in) per year. In the Sahel a steppe of thorny bushes (mostly acacias) gradually gives way to a savanna in Chad's Sudanese zone to the south. Yearly rainfall in this belt is over 900 mm (35 in). The region's tall grasses and extensive marshes make it favourable for birds, reptiles, and large mammals. Chad's major rivers—the Chari, Logone and their tributaries—flow through the southern savannas from the southeast into Lake Chad.