What is the default available network resources in Windows?

Can't understand why the available network resources ADMIN$, C$, IPC$ ? As you know, they are available initially for Windows, but why? What is the meaning of these accesses? The only thing I understand is access to administrative accounts on this computer with other computers, but I do not understand why is it a default? Is not harm the security of the OS?
Additional question - in the local network with hundreds of computers, whether to disable the normal components of these approaches?
July 2nd 19 at 13:57
2 answers
July 2nd 19 at 13:59
It is officially called "Administrative share", in addition to actually "live" administrators they can be used by different processes running from admin accounts. Since you have a network of a hundred computers, I will assume that it is the domain; after their removal in a domain network will have problems.
July 2nd 19 at 14:01
If the PC is in a domain to leave to control

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