Array between Unity and Mono?

Going deeper into the code I read this

In general, you’ll probably want to use
Mono’s Array object if you want flexibility, and Unity’s internal arrays if you want performance.

I thought that Unity was built on Mono and that the Mono class was the super class from which all the others were derived?
So what is the difference beween Unity Arrays and Mono Arrays?
At this stage I haven’t found comparatif between the two.
Also when using one or the other, is there a loss in precision from float in Unity to float in Mono?
Thanks
yves

Array is no implicit memory aligned array like [ ]. Its more comparable to javascripts and alikes array class and thats likely also its intend, to give Unityscript a functionality that web and action script devs might know well :slight_smile: