A random number generator is a piece of hardware that generates truely random numbers. There are several different approaches to designing the hardware, but listening to white noise and radioactive decays are populer approaches. Some of the RandomNumberGenerators avaliable on the web include:
/dev/random? is NOT an interface to a RandomNumberGenerator, it's an interface to a very good PseudoRandomNumberGenerator?, which is feed the randomness of network traffic, interupt timings and other low-level stuff that only the Kernel really has proper access to.
See also: random(3), rand(3), Cryptography
4 pages link to RandomNumberGenerator:
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