System

• id: know yourself
• w: who is logged in (-f to find where they are logging in from)
• lsblk: list block storage devices
• lscpu: display info about the CPUs
• lstopo: display hardware topology (need hwloc, hwloc-gui packages)
• free: free and used memory (try free -g)
• lsb_release -a : distribution info (sometimes not available)