Baseballs are the most essential thing on the diamond, so it’s important to find the right one. Younger ballplayers typically use a baseball with a soft core to reduce the risk of injury from impact. They’ll graduate to a ball with a solid core around the age of middle school.
High school and collegiate leagues have may have their own specifications for baseballs, so it’s key to know what those are. For example, the NCAA and MLB have started using balls with flatter seams in recent years in order to increase offensive numbers without leading to an outright offensive explosion.