Shell & Filesystem

Everything hangs off /. Key paths: /etc config, /home users, /var/log logs, /tmp scratch.

Essentials: ls -la (hidden + permissions), find / -name 'flag*' 2>/dev/null, grep -ri secret /etc. 2>/dev/null discards stderr (fd 2) to silence permission-denied noise. A leading dot hides a file — always list with -la.