Admins would get mad very quickly if they had to physically access every machine they needed to configure or patch. Admin shares are hidden folders to be accessed remotely, typically over SMB.
ADMIN$
This share maps to 📂 C:\Windows (%SystemRoot%). It’s typically used for remote administration and viewing the logs from another machine.
C$
It is a share of the root directory of the system drive (typically C:) and is used for administrative tasks.
IPC$
This one shares the named pipes necessary for network communication between programs and computers. IPC stands for InterProcess Communication. It is used during remote IPC (and can be empty). To access ADMIN$, one usually establishes the connection over IPC$.