If a base runner touches each base in the correct order he scores a run for his team. Remember that the team with the most runs at the end of the game is the winner. A run is worth one point for the offense. Teams can only score runs when they are at bat in their half-inning. The away team always bats first in a game. The defense who is fielding can not score runs, since they are not batting.
Batting and Base Running
To score a run in baseball, a batter must successfully hit a pitch into fair territory. Once the batter makes a hit, he must get on base and become a base runner. There are lots of batter types and ways to get on base. Since hits are one way to advance bases (and advancing enough bases eventually leads to scoring), batters attempt to hit the ball during their at-bat. To do this, the batter swings at pitches that are thrown by the pitcher and caught by the catcher. However, certain plays lead to the batter being out, ending his turn to hit or advance bases. When three outs are made, the half-inning is over.
A batter can automatically earn a run for his team if he hits a home run. A home run is when a batter hits the ball beyond the outfield fence. If there are base runners occupying bases when the batter hits a home run, they are all allowed to advance home to earn a run. For example, if there are runners are first base, second base, and third base, when a home run is hit, four runs are scored on the play. This is called a grand slam and is very rare in baseball.
Sometimes, a run can be scored with a great hit that stays inside the ballpark. An in the park home run is when a batter hits the ball and it stays inside the field, but is such a great hit that it gives the batter enough time to touch all of the bases. Inside the park home runs are also rare like grand slams.
Force in baseball is when a base runner gets out because he must occupy a base that another base runner is occupying. For example, there is a runner on first base and the batter hits a fair ball. The batter must occupy first base and the runner must occupy second base. There is force at both first base and second base. A fielder with the ball can simply touch the base for a force out.
A run will not count if a force out play is made giving the defense their third out of the inning. This rule holds true even if the base runner touches home plate prior to the force out being made. This is not the case with a tag out.
Imagine this scenario. There is a runner on first base and third base and there is one outs. The batter hits a flyball and it's caught. The runner on third base performs a tag up and scores a run, but the runner on first base is tagged out when trying to tag up at first base. If the runner on third base scores the run before the tag out, then it will still count since it is not a force out.