You must understand permissions if you are managing an LMS (as some of my students will do when they graduate). Thus I am posting this from last night’s class:
Three types of users: User – Group – World
These permissions can be given for one group, multiple groups, one user, etc.
Three types of permissions: Read (R or 4), Write ( W or 2), Execute (X or 1)
Sometimes written as – RWX or a number equivalent such as 777. Each word corresponds to a number depicted below that can add up to 7 (4+2+1).
R- Read (4) – read files
W- Write (2) – write/modify files
X – execute (1) -Read/write/delete/modify/directory
-r–rwx—- = User can read, group can do everything, world cannot access
777 = Everyone can do everything
422 =User can read, group can write, world can write
Rwx-rwx-rwx = Everyone can do everything
-wx-r—– = User can write and execute, group can read, world cannot access