Abstract—The use of random numbers is essential in randomized algorithms, and many statistical methods are using them on random sampling, this is due to the fact that examining all the possible cases is unpractical. Nowadays, the most common used of random numbers is in simulation studies of stochastic processes. In fact, the security of many cryptographic systems relies on the generating of random numbers. However, cryptographic applications require random numbers with different criteria than those used in simulation. This study investigates pseudo-random numbers PRN, Quasi-random numbers QRN, and cryptographic random numbers CRN. The survey goal is to cover several random number generators and examining their statistic proprietaries using several testing algorithms. Index Terms—Pseudo-random numbers PRN, Quasi-random numbers QRN, Pseudo-random number generators PRNG