The Boston Celtics are a professional basketball team based in Boston, Massachusetts. They play in the National Basketball Association (NBA). Their 16 NBA championships are the most for any NBA franchise. The Boston Celtics have had a rivalry, especially throughout the 80s, with the Los Angeles Lakers. At the height of the rivalry, the Lakers and Celtics won 8 of the 9 NBA Championships awarded from 1980-1988 (the Lakers won 5 while the Celtics won 3), and played each other in the NBA Finals on 3 occasions. The rivalry cooled off as the Celtics slipped into mediocrity in the mid and late-90s, but Lakers-Celtics is considered by many NBA fans to be the league's greatest rivalry. Another fierce rivalry formed in the 1980's between the Celtics and the Detroit Pistons. The two franchises met in the playoffs 5 times between 1985 and 1991. The rivalry, like their rivaly with the Lakers, cooled in the 90s but saw a resurgence in 2002 when the teams met in the Eastern Conference Semi-finals. The Celtics also have historical ties with the Philadelphia 76ers, who played the Celtics in tense playoff series in the 60s, 80s and 2000s. Full Article on Wikipedia