What do the stickers on curling stones mean?

Curling Stone Stickers

If you have gone to a curling club or watched curling on television, you may have noticed that each curling stone has two stickers on the handle - one is a letter, and the other is a number. This is because each stone has its own, "personal" set of characteristics. For example, Stone A, Number 3, may curl slightly more than Stone A, Number 6. This also allows the skip to keep track of how each rock behaves, which makes it easier to call the shot.

It is expected that the stones are thrown in order. By having a number on them, it is easy for the thrower to select the correct rock when throwing. At curling clubs, it is typical for the stones to remain on the same sheet of ice the entire time. Therefore, if a stone is on the wrong sheet, it can easily be moved back to its correct sheet, indicated by the letter on the sticker.