What Is An Apple Public Server?

I’m looking at the development menu of Safari on my Mac and pretty much every Apple branded url has header/server information detailing an “Apple Public Server” or an “Apple HTTP Server”. What I am seeing specifically is, “Apple Public Server RSA CA 1 - G1” and “AppleHTTPServer/37b150bd0775”

Does anyone know what these are? How do I unenroll from these?

Thank you!

-Blair