Definition
PPS pays miners a fixed amount for each share submitted, calculated from the theoretical value of that share based on the current block subsidy and difficulty. Unlike FPPS, PPS does not include transaction fees in the payout.
PPS provides highly predictable income for miners since payments are made per share regardless of block finds. However, miners miss out on transaction fee revenue, which can be significant during periods of high network activity. PPS has largely been superseded by FPPS at major pools.
In Simple Terms
A pool payout paying a fixed rate per share based on the block subsidy only, not transaction fees.
Pay Per Share. A pool payout method where miners are paid a fixed amount for each valid share submitted, based only on the block subsidy (not transaction fees).