These are some commands that I like to run through when I am fiddling around on a Linux machine.
output computer name
hostname
inspect network interfaces
ifconfig
show current working directory
pwd
change editor to VIM
export EDITOR=vim
list all users
cat /etc/passwd
add a user, grant sudo, delete the user, confirm deletion
useradd kata_user --create-home --user-group
usermod -aG sudo kata_user
userdel --remove kata_user
grep kata /etc/passwd
grep kata /etc/sudoers
find /home -maxdepth 1 -type d -name kata*
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