A golf Grand Slam refers to winning all four of golf's major championships. There are two main types: 1. Calendar-Year Grand Slam: Winning all four major tournaments-the Masters Tournament, the U.S. Open, The Open Championship (British Open), and the PGA Championship-in the same calendar year. This is extremely rare; the only player to achieve this was Bobby Jones in 1930, though the majors then included amateur championships rather than the current four professional majors

. 2. Career Grand Slam: Winning each of the four majors at least once over the course of a golfer's career. This is more common than the calendar- year slam but still a prestigious and difficult achievement. Only six male golfers have completed the modern career Grand Slam: Gene Sarazen, Ben Hogan, Gary Player, Jack Nicklaus, Tiger Woods, and Rory McIlroy (who completed it in 2025)

. Additionally, Tiger Woods held all four major titles simultaneously across two calendar years (2000–2001), a feat sometimes called the "Tiger Slam," though not a calendar-year Grand Slam

. In summary, the Grand Slam in golf signifies either winning all four majors in one year or winning each major at least once in a career, with the modern majors being the Masters, U.S. Open, The Open Championship, and PGA Championship