The primary concern of the batsman on strike (i.e., the "striker") is to prevent the ball hitting the wicket and secondarily to score runs by hitting the ball with his bat so that he and his partner have time to run from one end of the pitch to the other before the fielding side can return the ball. To register a run, both runners must touch the ground behind the crease with either their bats or their bodies (the batsmen carry their bats as they run). Each completed run increments the score.
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