The Major Championships, often referred to simply as "the majors", are the four most prestigious annual tournaments in professional golf. The "majors" originally consisted of the Open Championship, the British Amateur or The Amateur Championship, the U.S. Open and the US Amateur. With the introduction of the Masters Tournament in 1934, and the rise of professional golf in the late 1940s and 1950s, the term "major championships" eventually came to describe the Masters, the U.S. Open, the (British) Open Championship, and the (U.S.) PGA Championship. It is difficult to determine when the definition changed to include the current four tournaments, although many trace it to Arnold Palmer's 1960 season, when after winning the Masters and the U.S. Open to start the season he remarked that if he could win the Open Championship and PGA Championship to finish the season, he would complete "a grand slam of his own" to rival Bobby Jones's 1930 feat.

The oldest of the majors is The Open Championship, which is often referred to as the "British Open" outside the United Kingdom. Because of a lack of participation by American players due to the overseas travel times, the Open Championship was not considered a major in the U.S. until the early 1960s, when Arnold Palmer began competing in Great Britain. Until that time, many U.S. players considered the Western Open as one of golf's majors. It was Palmer and Pittsburgh golf writer Bob Drum who decided which four events would comprise the modern four majors and rekindled the Grand Slam of Golf concept.

The other three majors all take place in the United States. The Masters (often known as the "U.S. Masters" outside North America) is played at the same course, Augusta National Golf Club, every year, while the other three rotate courses (the Open Championship, however, is always played on a links course). Each of the majors has a distinct history, and they are run by four different golfing organizations, but their special status is recognized worldwide. Major championship winners receive the maximum possible allocation of 50 points from the Official World Golf Rankings, which are endorsed by all of the main tours, and major championship prize money is official on the three richest regular (ie under-50) golf tours, the PGA Tour, European Tour and Japan Golf Tour. In order of their playing date the majors are:

1. April - The Masters (weekend ending 2nd Sunday in April) - hosted as an invitational by and played at Augusta National Golf Club
2. June - U.S. Open (weekend ending with the 3rd Sunday in June) - hosted by the USGA and played at various locations in the USA
3. July - The Open Championship (weekend containing the 3rd Friday in July) - hosted by the R&A and always played on a links course at various locations in the UK
4. August - PGA Championship (4th weekend after the Open Championship) - hosted by the Professional Golfers' Association of America and played at various locations in the USA.

Alongside the biennial Ryder Cup and Presidents Cup team competitions, the majors are golf's marquee events. Elite players from all over the world participate in them, and the reputations of the greatest players in golf history are largely based on the number of major championship victories they accumulate. The top prizes are not actually the largest in golf, being surpassed by the Players Championship, the three individual World Golf Championships events, and one or two invitational events, but winning a major boosts a player's career far more than winning any other tournament. If he is already a leading player, he will probably receive large bonuses from his sponsors and may be able to negotiate better contracts. If he is an unknown he will immediately be signed up. Perhaps more importantly, he will receive an exemption from the need to annually requalify for a tour card on his home tour, thus giving a tournament golfer some security in an unstable profession. Currently the PGA Tour gives a five-year exemption to all major winners.

In recent years the Players Championship, which was held two weeks before the Masters, has been begun to be boosted as "the fifth major" by elements of the American media. This has not been publicly encouraged by golf authorities, but the tournament does attract a similar strength of field. With "The Players" move to mid-May in 2007, some people (mainly in North America) believe that the Players should be considered a de facto major championship, even if it's not considered part of "the grand slam". Outside the United States, the idea of increasing the proportion of majors held in the U.S. from three out of four to four out of five is much less popular. In addition, three World Golf Championship events were established in 1999, bringing to eight the total number of events in which virtually all of the world's top few dozen players compete against each other every year.