Phase 2 opened — first steps into Linux

What I got through

• A1 — Filesystem hierarchy (/proc, /sys, /dev, /etc, /var, /usr). Quizzed myself and got 5 of 6 trace answers right unaided in one sitting; /dev took five attempts before the "device" vs. "driver" wording and the boot-or-hotplug detail both stuck, and I set aside the deeper /sys material (kobject/kref/uevent) as pulled-forward Phase 4/5 content rather than drilling it at full depth right now.
• A2 — Daily navigation (ls -la, cd, cp, mv, rm -r, mkdir -p, globbing). Ran myself through three trace questions, all unaided. Ran the practice round in WSL for the first time instead of just on paper.
• A3 — find & grep. Ran myself through three trace questions, all unaided, also run in WSL. Confirmed the shell expands globs before find ever sees them, so a pattern meant for find itself has to be quoted.
• A4 — Permissions (rwx, chmod octal + symbolic, group, sticky bit). Ran myself through three trace questions, all unaided (one retry computing 750 in octal).

Mistakes I made

• Taught myself cp's trailing-slash behaviour as if it were rsync's — cp -r behaves identically with or without a trailing slash on the source; rsync is the tool where that distinction actually matters.
• Assumed chmod +x with no class letter meant the same thing as a+x. It doesn't — with no class given, it defers to the process's umask. Confirmed live under umask 011.
• Kept saying "character/block driver" when I meant "character/block device" — the node in /dev classifies the device type; the driver is separate code entirely.

What's next

WSL (Ubuntu) is confirmed working on my own laptop — prompt darsh@loq:~$, both practice rounds ran clean there. Next byte is A5, hard vs. soft links, tagged high-priority. VirtualBox stays parked until Phase 4, when kernel modules actually need a real kernel tree to build against.