In baseball, a contact hitter is a hitter who does not strike out often. Thus, they are usually able to use their bats to make contact with the ball (hence the name contact hitter) and put it in play. As a result of their focus on putting the ball in play, they usually have fewer home runs than power hitters.
Tony Gwynn is the leading example of a modern contact hitter. Although he had 135 career home runs, Gwynn accurately described himself as a contact hitter who could hit to all fields. He rarely struck out (just 434 times, once every 21 at-bats) and his goal was to put the ball in play and move baserunners over. Gwynn's success as a contact hitter landed him in the National Baseball Hall of Fame.