In severalteam sports,matches are played in two halves.Half-time (also writtenhalftime orhalf time) is the name given to the interval between the two halves of the match. Typically, after half-time, teams swap ends of the field of play in order to reduce any advantage that may be gained from wind or a slope to the playing surface, for example.

While it exists mainly to allow competitors to rest briefly and recover from the play of the first half, half-time also serves a number of other purposes. It also serves as anintermission for spectators, and, especially in North America, often featuresentertainment, such ascheerleading performances,tifos, performances by schoolmarching bands (particularly in high school andcollegiate sports in North America), or concerts featuring popular music acts (particularly in major events such as theSuper Bowl). On games that are broadcast on television and radio, it also provides broadcasters with an opportunity to give a recap of the first half of the game, air highlights of other games in progress, aircommercials and other advertisements, provide analysis on the game, or air game-related festivities (such as an aforementioned half-time performance).

The main origin of changing ends at half-time lies in the earlyEnglish Public School football games. One early use of afixed half-time (as suggested by Adrian Harvey in his book, Football, The First Hundred Years: The Untold Story) is that the origin of the practice was to allow for two football teams each used to a different set of rules to play half of the game by familiar rules, and half by the opposition rules. This was practised notably between followers ofEton-rules football (closer to modern association football) andRugby-rules football (closer to modern rugbyRugby union). This particular use of half-time could be seen as unnecessary after the standardisation of football rules (and indeed, the first set of FA Laws in 1863 did not provide for a half time interval) but is still used for the now-rare contests between teams playing different codes of football. Provision for a half time interval in FA Laws was introduced in 1870 and has been part of those Laws (and later, IFAB Laws) ever since (seeLaws of the Game). Changing ends at half-time (if no goals had been scored) was part of the following schools' codes: Brighton, Eton, Rossall, Sheffield, and Winchester. Other schools changed every time that side scored (Cheltenham, FA, Harrow, Marlborough, Rugby, Shrewsbury, Uppingham schools)^[1] The 1863Cambridge Rules state: "In a match when half the time agreed upon has elapsed, the side shall change goals when the ball is next out of play".

One benefit of half-time in a field game is to allow teams to swap their positions on the field in order that the effects of the natural conditions such as sunlight and wind direction are experienced fairly by both teams. In some sports this is achieved without the need for half-time: for example, incricket fielding positions of players are rotated after a set passage of play. In other sports no such provision is necessary, for example inbaseball, where playing positions do not change and both teams occupy the same locations on the field of play, though there is frequent rotation of players in the ordinary course of play.

Half-time for spectators offers the opportunity to visit the toilet, get some food or drink, or just exercisecrampedlimbs, without the fear of missing any of the action. Ahalf-time show may be put on for the spectators to keep their attention, most famously in the case of theAmerican footballSuper Bowl. As many spectators at the ground may be otherwise occupied using stadium facilities it might be inferred^{[by whom?]} that the scale and spectacle of half-time entertainment is more directly related to the size of the potential television audience.

In many sports that aretelevised, half-time offers the opportunity to advertise, a valuable source ofrevenue fortelevisioncompanies. In addition, it allows analysis of the game so far by pundits; controversial incidents or exceptional play may be highlighted at this time. It also allows viewers to catch up with any action that they may have missed. Half-time has spawned one of the most enduringclichés to describe football: that "it's a game of two halves."^[2]

• Ice hockey is played in three periods of twenty minutes with eighteen-minute intermissions between regulation periods.
• Water polo^{[citation needed]}
• Test cricket
• Box lacrosse
• Volleyball matches typically take three minutes between sets 1 and 2 and any sets after the 3rd (if played). The interval between sets 2 and 3 is sometimes longer and sometimes the same.

(other than to allow movement of players in the natural course of play and/or TV commercials)

• Baseball (although there is aseventh-inning stretch)
• Softball