History
Rounders is, almost unquestionably, baseball's immediate ancestor. Primarily a boys' sport in England, it was mentioned, along with baseball, in a 1744 publication, A Little Pretty Pocket-Book, and the sport was explained in detail in the second edition of The Boy's Own Book, published in 1828.
It's quite likely that both rounders and cricket evolved from stoolball, though there's no direct evidence that they did.
Henry Chadwick, a native of England who became the first newspaper writer to cover baseball, wrote a historical piece for Spalding's Baseball Guide in 1903, in which he asserted that baseball had derive from rounders. The assertion angered his publisher, A. G. Spalding, who insisted that baseball must be a thoroughly American sport.
Spalding called for a commission to investigate the origins of "the great American pastime," and it was this commission that decided in 1907 that Abner Doubleday had invented the sport. So Chadwick's undoubtedly true statement ironically led to the creation of a total myth.
Incidentally, Spalding should have known better. He was among a group of baseball players who visited England in 1874, when English spectators and sportswriters all recognized the "American" sport as a variation on rounders. And in 1889 Spalding was on an American team that played a game against a champion English rounders team in Liverpool.
The Scottish Rounders Association was founded in 1889 and a National Rounders Association was established in England in 1943. However, rounders remains primarily a sport for schoolboys and schoolgirls.
The Game
There are four posts in rounders, but the field is laid out as a pentagon with one open side. The batsman stands at a batting square, 28 feet from the front of the bowling square.
The bowler is supposed to throw the ball over the batting square, above the knee and below the head of the batsman. If he does, the batsman is supposed to try to hit the ball.
Even if he doesn't swing at a legal pich, or if he swings and misses, the batsman has to run to the first post. As in baseball, he then tries to proceed to the second, third, and fourth posts. However, the fourth post is not where he started out. It's 28 feet to the left of the batting square.
There's no such as foul territory in rounders. If the batted ball goes behind the batting square, the batsman can run only as far as first post until the ball is thrown back into the forward area.
A runner is put out if his batted ball is caught in the fly, if a fielder touches him with the ball between posts, or if the post toward which he's running is touched with the ball by a fielder. Three bad pitches entitle the batsman to move to the second post; that's called "half a rounder," and circling the posts is a "rounder," which scores one point.
There are nine players on a team and nine outs in an inning. Two innings make up a match.