Online casinos use RNG or Random Number Generator for creating outcomes in gambling games. Slot machines, video poker, online roulette use Pseudo RNG which is entirely different from True RNG or Hardware RNG. These software codes are encrypted in cryptography to make them perfectly random and consider temperature and atmospheric pressure while producing a number. They eliminate human biases from the game.
A PRNG is a software that produces numbers that appear random, but in reality, they are predetermined by a number known as ‘Seed’. The series of random numbers so generated by RNGs come from a fixed number. Classically, Dice and Coins are considered hardware Random Number Generators.