An STP (Straight-Through Processing) broker routes client orders directly to external liquidity providers rather than taking the other side of the trade internally, typically earning revenue from a small markup on the raw spread. It sits between a market maker (which internalizes orders) and a full ECN (which offers direct depth-of-market access), usually with simpler all-in pricing than a raw-spread-plus-commission ECN account.
Because the broker isn't taking the opposite side of the trade, STP execution removes the structural conflict of interest that comes with a dealing-desk model.
Next step
Guide
How a Broker Holds Your Money
Segregated accounts, regulatory capital and compensation schemes are three different protections that get described in one sentence. What each covers, what it does not, and how to check which apply to you.