Read permission r = 4
Write permission w = 2
Execution permission x = 1
775 These three numbers represent the permissions of the owner, group users, and other users.
For example:
7 The owner has read, write, and execute permissions
7 groups of users have read, write, and execute permissions
5 Other users have read and execute permissions (4+1 = 5)
The difference between 777 and 775 is
Other users have write permissions, while 775's do not.
For example:
File A, permission is 775
root is the owner
www-data is the group user
ooo is another user
So
root, www-data, and ooo can read and execute file A.
root,www-data can write to file A.
ooo cannot be written to file A.
If it is 777
Then all three users can read, write, and execute file A
Write permission w = 2
Execution permission x = 1
775 These three numbers represent the permissions of the owner, group users, and other users.
For example:
7 The owner has read, write, and execute permissions
7 groups of users have read, write, and execute permissions
5 Other users have read and execute permissions (4+1 = 5)
The difference between 777 and 775 is
Other users have write permissions, while 775's do not.
For example:
File A, permission is 775
root is the owner
www-data is the group user
ooo is another user
So
root, www-data, and ooo can read and execute file A.
root,www-data can write to file A.
ooo cannot be written to file A.
If it is 777
Then all three users can read, write, and execute file A