On Ubuntu how to set folder permission?

On Ubuntu 

how to set folder permission?

you can using the command on below:

sudo chown -R username:group directory




for example, user tommy on Homegroup:

sudo chown -R tommy:Homegroup directory

but the group is not a required parameter.

ref: https://askubuntu.com/questions/6723/change-folder-permissions-and-ownership

how to list all local users?

cut -d: -f1 /etc/passwd




ref: https://askubuntu.com/questions/410244/is-there-a-command-to-list-all-users-also-to-add-delete-modify-users-in-the