Fond out that there is not one but 2 versions of Perlin noise as seen here
Since the second one is the improved version of the first one, I was wondering witch one Unity3D is currently using as I use it quite a lot and was wondering if I should make my own version of it.
AFAIK, there is no such a thing as a "version" of perlin noise.
Originally, "Perlin noise" refered to one specific algorithm, developed by Ken Perlin, to generate gradient noise.
Nowadays, the term "perlin noise" is used to describe a wide range of modified and/or tweaked implementations of the original algorithm.
I don't know what you mean by "first one" and "second one". Your question is malformed.
The question you should probably ask instead is:
"How is Perlin noise implemented in unity?"
