what does the line that runs parallel to the first base line mean?

Question

why isnt there a similar line for the third base line?

Answer 1

It's rule 6.05.k, which states:

k) In running the last half of the distance from home base to first base, while the ball is being fielded to first base, he runs outside (to the right of) the three-foot line, or inside (to the left of) the foul line, and in the umpire’s judgment in so doing interferes with the fielder taking the throw at first base, in which case the ball is dead; except that he may run outside (to the right of) the threefoot line or inside (to the left of) the foul line to avoid a fielder attempting to field a batted ball;
Rule 6.05(k) Comment: The lines marking the three-foot lane are a part of that lane and a batter-runner is required to have both feet within the three-foot lane or on the lines marking the lane.

There's no comparable line between third and home for a couple of reasons:

1) For a runner rounding third and heading home, there's no way they could make the turn so tightly as to stay inside the lines, and

2) The possibility of interference by the runner doesn't exist at home as much as it does on a play at first base.

Answer 2

That is the 45 foot line. It starts halfway down the first base line. The base runner has to stay in it or less he is out. This is there so that if a pitcher fields a ground ball and tries to tag the runner out, the runner cant go way outside the line. Also, if there is a bunt or something that the catcher fields, the line keeps the runner from obstructing the throw to first base.

Answer 3

Thats where the base runner has to be running if there is a bunt or strikeout and the catcher drops the ball. Its there so the catcher or even pitcher has a clear lane to throw the ball to first.

If the player runs inside (to the left of the fould line) he can be called out automatically because he did not run in the box

Answer 4

The line is where the base runner must be when running to first. If he is over the line and is hit by the ball while running to first he is out for interfering with the throw.

Answer 5

It means that the fans cannot cross the line or they will get tackled by security

Answer 6

its a baserunners line