MacTeX is a redistribution of TeX Live with a Mac-specific installer,
TeXShop, and a few other Mac-only extras. See
https://tug.org/mactex/ and https://ctan.org/pkg/mactex for more.

Also https://ctan.org/pkg/mactex-basic for the BasicTeX distribution, a
severely cut-down, but still functional, version of MacTeX.

Also https://ctan.org/pkg/mactextras for the auxiliary distribution here
of software not included in MacTeX.