A private server is basicaly you're own version of runescape
You can Modify it like you wish eg. add quick leveling like clicking on something
Add Codes to spawn Items Spawn Monsters
Basicaly you can do anything
People make diffirent servers pk servers cw servers and chill servers
when u open Moparscape the Default Ip is Moparscapes Version
you cant Log in with friends but u can spawn items ect
Joining Someelses Network
The Person Should Give you a Hamachia Name
Hamachia Is A Runescape Server Checker Thingo
So With hamachia you Click Join existing Network
Type in the Username of the Network
and then Type the pass Normaly 123 but owner will provide
Then Look for a Person On the Server it Should Say Ip 232.3232.334 or Somother Ip
Type that into the Ip Box If its got a port Go to the top Of The Moparscape Page and Click File New Port 4343 (4 Digit )
Then Make Up a username
and Make Up a Pass Any Connect
If it doesnt work the server is Down So Just Try Agian Later
Creating You're Own server
I have been Trying to find this out aswell i dont know how to make One LOl
So I cant help u there

Hoped I Helped