What exactly issues "no_root_squash" would cause? and how to disable it?

-  What exactly issues "no_root_squash" would cause, please show me an example, and how to disable it?

-  Is following enabling "no_root_squash", and why?

Client Match Hostname, IP Address, Netgroup, or Domain: 0.0.0.0/0  all clients

RO Access Rule: sys,none  AUTH_SYS and AUTH_NONE allowed

RW Access Rule: sys,none  AUTH_SYS and AUTH_NONE allowed

User ID To Which Anonymous Users Are Mapped: 65534  mapped to 65534

Superuser Security Types: sys  superuser for AUTH_SYS only

- what about If I remove "none" in RO and RW in above settings? by doing that,  would it disable "no_root_squash" and why?

Somebody please shed a light on these questions, they really bother me. Thanks!