On Linux/Unix-based operating systems, every file belongs to a user and to a group. By default, the user who creates the file is the owner of that file and the file belongs to that user's primary group. Access to the file via the Linux filesystem is controlled by permissions applied to that file. These permissions are classified for the owner (also known as the user) of the file, group (also known as the group owner) of that file, and for everybody else (also known as others) in the Linux system.
There are three types of standard permissions that are applied to files:
- Read, represented by the letter r
- Write, represented by the letter w
- Execute, represented by the letter x
These are generally grouped in triplets (such as rwx or r-w) to represent a class of permissions. Each file has three classes of permissions; that is, these permissions...