Skip to content

Users & Access

Every operation on a Linux system is governed by three things: who you are, what group you belong to, and what the file allows. The two articles here cover both sides of that equation — the permission model itself, and the identity system behind it.

  • File Permissions

    Read the rwxr-xr-x strings, change permissions with chmod, and understand the difference between symbolic and octal notation — and when each is right.

  • Users and Groups

    Add users, manage groups, switch identities with sudo and su, and understand how Linux maps identity to access at runtime.

What's Next

With permissions and identity in hand, the next step is working with data. Head to Text & Pipelines — the Linux tools for filtering, routing, and searching the output of any command.