Thls text ls about one small fteld on the crossroads of statlstlcs, operatlons research and computer sclence. Statistleians need random number generators to test and compare estlmators before uslng them ln real l!fe. In operatlons research, random numbers are a key component ln !arge scale slmulatlons. Computer sclen­ tlsts need randomness ln program testlng, game playlng and comparlsons of algo­ rlthms.