Linux Administration · Module 1 of 10

Linux basics

Linux is the free operating system that runs most servers and the cloud.

📖 Key ideas

Linux is an open-source OS kernel; distributions add tools (Ubuntu, Debian, RHEL, Rocky, Fedora).
Most web servers, cloud VMs and Android use Linux.
Everything is a file, organised from the root /.
Key folders: /etc (config), /home (users), /var (logs, data), /usr (programs).
Admins work mostly in the terminal over SSH.

💡 Real-life example: Linux is the engine under most of the internet's cars; distributions are different car models using it.

KernelCore of the operating system

DistributionLinux kernel plus tools packaged

/etcConfiguration folder

SSHSecure remote shell