A pseudo-random number generator (PRNG) is a deterministic algorithm capable of generating sequences of numbers that approximate the properties of random numbers. Each sequence is completely determined by the initial state of the PRNG and the algorithm for changing the state. Most PRNGs make it possible to set the initial state, also referred to as the "seed state." This is referred to as "seeding" the PRNG.
Calling a PRNG that is not seeded in the same initial state, either without seeding it explicitly, or by seeding with the same value results in generating the same sequence of random numbers in different runs of the program.
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