What are the odds of that??

[DirectorTsaarx]

Most computerized random-number generators use a complex formula that takes a "seed" value and comes up with a "pseudo-random" number. This "pseudo-random" number is then used as the seed for the next number in the sequence, etc. So, really, a random-number generator merely creates a randomized sequence of numbers; not only is every number equally likely to occur, if you run through the whole sequence, you will get a perfect distribution of those numbers (i.e., actual occurrences will exactly match predicted occurrences). Obviously, for any set of runs less than the full sequence of numbers, the distribution is not necessarily perfect; in fact, as the set of runs approaches the full sequence, the distribution becomes more "perfect" and therefore less "random".

A pseudo-random sequence can be implemented in hardware using a shift register and some exclusive-OR gates connected as a feedback loop for the shift register.