What Makes a Foul Tip
A foul tip happens when the batter makes contact with a pitch and the ball travels directly into the catcher's glove or hand. The ball must go straight from the bat to the catcher without hitting the ground, the batter, or anything else first. This is different from a regular foul ball, which can go in any direction.
How It Counts
When a foul tip is caught, it counts as both a strike and an out. This means the batter is immediately out and the at-bat is over. The catcher does not need to throw the ball anywhere. If the foul tip is not caught and lands on the ground, it is treated as a regular foul ball.
When Foul Tips Occur
Foul tips most often happen on pitches that are close to the batter, especially pitches that are high or inside. The batter may be trying to make contact or just trying to protect against a close pitch. These plays are common in baseball and happen regularly during games.
Runner Rules
Even though a foul tip is an out, runners can still advance if they choose to. This is because the ball remains live during play. However, most runners stay in place after a foul tip since the batter is already out and there is no reason to take the extra risk.
Difference from Other Foul Balls
A foul tip is more difficult to catch than a regular foul ball because it must be caught directly from the bat. A regular foul ball can bounce on the ground or in the stands and still be an out if caught. Foul tips require quick reflexes from the catcher and are an important defensive skill. 
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