Baseball, by the Rules
Infield Single
The batter hits a ground ball that stays in the infield, but it’s hit to the exact perfect spot such that the defenders either can’t get to it in time, or if they make a play on it, the throw to first comes too late, and the batter gets a base hit: specifically, a single.
Because the batter running to first is a force play, the batter needs to touch the base before a fielder touches the base while in possession of the ball. For the vast majority of plays at first, this means the runner has to get there before the first baseman catches the ball.
One unique aspect about a play at first base— unlike the other bases, where the runner needs to stay on the base or risk being tagged out, a runner running to first can safely run through the bag and down the line. As long as that runner doesn’t make a move towards second base, they can decelerate safely and return to the base once the play is over, as long as they turn to the right (towards foul territory) in doing so. If they so much as flinch in the direction of second base, though, the defense can make a play on them. If the defense does get the out, is scored as a ground out, not a single. However, this is a rare play; the runner won’t have any reason to flinch towards second unless the defense makes a mistake somewhere.