In Baseball, how many times does the ball have to be pitched outside of the strike zone before the batter is walked?

In baseball, a batter is walked when the pitcher throws four pitches outside of the strike zone. This rule is in place to prevent pitchers from constantly throwing wild or inaccurate pitches, forcing them to throw strikes and provide opportunities for hitters to make contact with the ball. By requiring four pitches outside of the strike zone, it ensures that the batter has a fair chance to either swing at a good pitch or wait for a walk if the pitcher is consistently missing the strike zone.