Limit pricing
Setting prices low enough that they would make it unprofitable for new firms to enter the market. Deterring hit and run competition.
Firm might use limit pricing and remain profitable
If the incumbent firms in the industry enjoy significant economies of scale.
Predatory pricing
Prices are set so low that other firms already in the market are forced out of business by making a loss as they seek to complete.
Predatory pricing in the long run
The reduced competition will make it possible for the firm to increase its prices especially when other barriers to entry are high.