Random Numbers

Question

How do are random numbers generated in functions of many programming languages like Java, C++, C, C#, Python, ETC. Kindly explain that I am having a deep interest in this

Answer 1

Good article here: https://www.random.org/randomness/
and here:
https://en.m.wikipedia.org/wiki/Linear_congruential_generator

Answer 2

@Aayushman. Algorithms. See second link for an example of one commonly used method

Answer 3

I don't want to know how many random functions are there but want to know how they work