In Europe, the moves of the pieces changed in the 15th century. The modern game starts with these changes. In the second half of the 19th century, modern tournament play began. Chess clocks were first used in 1883, and the first world chess championship was held in 1886. The 20th century saw advances in chess theory, and the establishment of the World Chess Federation (FIDE). Chess engines (programs that play chess), and chess data bases became important.