Computers can only generate pseudo-random numbers. Various mathematical functions are used to create a sequence of pseudo-random numbers, and those functions often revolve around using logarithms. They are pseudo-random because although the sequence may appear random based of distribution and various statistics used to measure "randomness" of sequences of values, it's still a product of a certain function and the sequence is strictly deterministic and has a "rotation period" after which it simply repeats itself, which makes it possible for example to predict what the "random" number will be at any future position in the sequence, or what it was at any previous position if you know the number used to seed the generator.