The house edge is the casino's mathematical advantage, expressed as a percentage of each bet it expects to keep over time. A 2% edge means the game keeps $2 of every $100 wagered on average.
Edge vs RTP
House edge and RTP are two sides of the same coin: a 96% RTP slot has a 4% house edge. Lower edge games (blackjack, baccarat, European roulette) are friendlier to your bankroll than high-edge games. The edge is a long-run average — single sessions still swing both ways.