The Turks and Caicos Islands (/ˈtɜrks/ and /ˈkeɪkəs/ / /ˈkeɪkoʊs/ / /ˈkeɪkɒs/), or TCI for short, are a British Overseas Territory consisting of the larger Caicos Islands and smaller Turks Islands, two groups of tropical islands in the Lucayan Archipelago, part of the larger Antilles island grouping. They are known primarily for tourism and as an offshore financial centre. The resident population is about 31,500, of whom 23,769 live on Providenciales in the Caicos Islands.