The Playground

A pretend Linux server that runs in your browser. Switch between Rocky and Ubuntu in the title bar. You can't break anything, and Reset gives you a fresh machine.

Challenges

Find the treasure hidden in games/maze
Install cowsay on both families (each one has a catch)
Launch a website and curl localhost to see it
Lock yourself out with ufw on Ubuntu, then work out why
Type sl after installing it 🚂
Find which log file records logins on each family
Schedule a job with crontab -e, then timewarp 10m
Create a user, a group and a shared folder
Write a script, chmod +x it and run it
Back up Documents with tar and restore it

Handy

help: what the playground knows
explain CMD: plain-English tutor
man CMD: the manual
Tab completes, ↑ repeats
timewarp 1h: skip time (playground only)
sudo password: linux

This is a simulation. It copies real output and error messages closely, but it isn't a real Linux machine.