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Linux Permissions are much more simple than what is provided in Windows Active Directory. You have 3 permission types that you can apply to 3 groups. The permissions are Read, Write and Execute which can be applied to the file/folder Owner, the Group Owner and Everyone.

Permission Grouping

Permissions are applied by Owner/ Group Owner/ Everyone
To view permissions and owners use ls -l command in a folder.
Permissions

Execute – Allows script execution
Read – Allows the ability to read
Write – Allows to modify, rename and even delete
Permission Numbers

Execute = 1
Write = 2
Read = 4
Simply add numbers together to get cumulative permissions.

0 = – – –
1 = – – x
2 = – w –
3 = – w x
4 = r – –
5 = r – x
6 = r w –
7 = r w x
Examples

777 = Owner, Members of Group Owner, Everyone have Full Control
764 = Owner has Full Control, Group has Read and Write, Everyone has Read
740 = Owner has Full Control, Group can Read, Everyone can do nothing.