LBW refers to the method of blocking the ball by the batsman through the parts of the body that is going to hit the stump.
History
LBW was introduced when it was seen that batsmen stop the ball to hit the stump using their leg or feet. In 1975, the first batsmen were considered out through LBW rule.
Rules
Batsman is considered not out when there is no-ball, or ball hits the bat before hitting the pad. Batsman is considered out when if the ball hits the pad or he is been seeing given no stroke
Conditions for lbw
Ball thrown by the bowler must not be no-ball The ball must not be thrown focussing on the leg side of the batsman The ball must touch the batsman and must not strike the bat Ball must be thrown in a line
What do you mean by impact in LBW?
Impact in LBW is considered to that point when the ball hits the pad or any other part of the batsman's body. Various replays are done to see whether the impact of the ball was in line or not.
What is shot offered in LBW?
When a batsman gives some kind of response in order to protect himself from hitting the ball. This ball is considered as the dead ball.