Thomas & Friends is a media franchise created by Rev. W. Awdry and Britt Allcroft. The franchise revolves around a railway, called the North Western Railway, located on the fictional Island of Sodor. The current title character of the franchise is Thomas the Tank Engine, an anthropomorphised steam locomotive, who works with other engines, including Edward, Henry, Gordon, James, Percy, Toby and many others. The franchise began with stories told from Wilbert Awdry to his son. In 1984, it was turned into a television series, which spawned a reboot series, titled Thomas & Friends: All Engines Go.

Thomas the Tank Engine is an anthropomorphised fictional tank locomotive in the British Railway Series books by Wilbert Awdry and his son, Christopher, published from 1945. He became the most popular and famous character in the series, and is the titular protagonist in the accompanying television adaptation series Thomas & Friends and its reboot Thomas & Friends: All Engines Go.