Hit and run is a tactic consisting of joining a game, waiting for a big payoff, then leaving the table as soon as the pot is won. Thus, the opposition will not have a chance to make their money back in the short term.
This is seen by most players as displaying a lack of gaming prowess or will to take risks, and is also considered rather antisocial. On the otherhand, it can be quite profitable since it is based on making a win as quickly as possible and the retracting those winnings from the reach of the opposition.
Shorststack strategies, based on buying in with very little money and leaving as soon as the stack size is too large, are therefore also hit and run strategies.