Return to Player (RTP) is the theoretical percentage of all money wagered on a game that gets paid back to players as winnings — calculated over the game's full mathematical cycle, which typically means many millions of simulated rounds, not any single session you actually play.
A 96% RTP slot returns, on average, $96 for every $100 wagered across that entire cycle. That does not mean any individual session returns close to $96 — it could return $0 or it could return a jackpot worth thousands of times your bet. RTP describes the long-run average of the whole population of spins ever made on that game, not a promise about your next ten minutes.
RTP is also not the same thing as "house edge," which is simply 100% minus RTP — a 96% RTP game has a 4% house edge. Regulators such as the UK Gambling Commission and the Malta Gaming Authority require every licensed game's RNG and RTP figures to be independently tested and certified by accredited labs (organizations like GLI and eCOGRA do this testing) before it can be offered to real-money players, and that certified figure is what should be published on the game's own information screen — worth checking directly in-game rather than assuming a number from a review site is current.
