Base running is a fundamental skill in baseball and softball that involves players running between bases to score runs. It begins when a player hits the ball and must decide whether to advance to first base, second base, or beyond. Good base running requires speed, awareness of the game situation, and the ability to read the actions of fielders. Effective base running includes techniques such as rounding the bases efficiently and knowing when to take risks. Players must also understand the importance of tagging up on fly balls and how to slide safely into bases to avoid being tagged out.