[Mingw-msys] What is the difference between the tools in msys and mingw

[zwz <zha...@gm...>]

Hi, all

I use mingw+msys on Windows.
I find there are some tools in both msys and mingw, such as libtool,
autoconf, automake, xz, zlib etc..

This really confuses me. I do not know why there will be two versions.
What is the difference? Which one should I use?

I guess this also bothers some new users, so I bring up the problem
here.