A high quality, high speed pseudorandom number generator. The specific implementation in Grasshopper is the Xoshiro256**, as published by D. Blackman and S. Vigna in 2018. The algorithm is named after its principal operations eXclusive-Or, Shift and Rotate and represents a different -and generally better- approach to pseudorandom sequences than both the Linear Congruential and Well Equidistributed Long-Period Linear algorithm families. Xoshiro is the default generator in Grasshopper 2.