text: Randomness, or complete unpredictability, in different fields have different meaning and significance. \n\nMany scientific fields are concerned with randomness:\n\nAlgorithmic probability \nChaos theory \nCryptography \nGame theory \nInformation theory \nPattern recognition \nProbability theory \nQuantum mechanics \nStatistics \nStatistical mechanics \n(You can read about this in the first link)\n\nIMHO, there is no way to generate truly random numbers if you are thinking of generating millions of numbers (in any large data set, one is sure to find some kind of statistical pattern). The closest we can get to complete randomness is a hardware pseudorandom process (see second and third link).