Random

Random[] gives a uniformly distributed pseudorandom Real in the range 0 to 1. 

Random[type,range] gives a pseudorandom number of the specified type, lying in the specified range. Possible types are: Integer, Real and Complex. The default range is 0 to 1. You can give the range {min,max} explicitly; a range specification of max is equivalent to {0,max}. 

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