Well, random numbers are usually not random. While computers can generate “true” random numbers, this needs to be based on a physical phenomenon that is completely random in nature. However, most applications just use pseudorandom numbers, which are just random enough. Like, does your game really have to be cryptographically accurate?

“True” random numbers are generally used only for cryptographic purposes where any vector of predictability can cause some serious issues. The source of entropy for modern-day computers is simply just atmospheric noise or patterns in your activity such as keystrokes and cursor movements.

So, what about the “false” random numbers? These are called pseudorandom because they are mathematically computed using a seed and various algorithms. Now, this is obviously faster because we are not dependent on any external source of entropy, making it suitable when the lack of randomness isn’t going to burn all my money or kill me.