np.random.seed(200) what is the use of seed in above line.and why 200 only...?? code example

Example 1: set seed numpy

numpy.random.seed()

Example 2: numpy random normal seed time

>>> numpy.random.seed(0) ; numpy.random.rand(4)
array([ 0.55,  0.72,  0.6 ,  0.54])
>>> numpy.random.seed(0) ; numpy.random.rand(4)
array([ 0.55,  0.72,  0.6 ,  0.54])