The different permissions

There are 3 permissions that someone can have for a file:

• Read: the user can read the contents of the file.
• Write: the user can change the contents of the file, or delete it.
• Execute: the user can treat the file like a command to be executed.

A simple example will illustrate the point. Suppose I am working on a programming project of some kind with my classmates. We have a file, project.c, that is part of the project. The file is owned by my user and the group is my_team.

• User: I want to be able to both read and change the file.
• Group: I also want my teammates to be able to read and change the file.
• Others: I want the web server (running as user www-data) to be able to read the file so that I can publish it on the web for my lecturer.

So how do I set the permissions? Stay tuned for how to change permissions.