What does HLP mean?

HLP is an acronym for "Haste Leaderboard Payout" and is the incentive mechanism made popular and patented by the Haste founding team. In short, HLP uses micropayments to payout leaderboards in gaming, loyalty reward programs, and practically any other competitive-based system you can think of. 

Here is an awesome article that was written shortly after the original alpha game, "Haste", was introduced publically as the world's first HLP game. It was this game that ultimately led to the idea for developing the Haste Arcade platform & SDK.