ls - list storage
pwd - present working directory
cd - change directory
file - to know file type
locate - locate the file
which - command to find a command
history - history of commands
whatis - to get what command does
appropos - command to get info about command what it does
man - manual page
mkdir - create a directory
touch - create a empty file / update date on a file
cp - createa copy of file / edit a file without removing
mv - move a file / rename a file
rm -r direct_name ->remove a directory
rmdir - remove a directory if it contains nothing
cat - concatenate
sudo - super user do
chmod - change a mode
users - who are logged into system
killall - kill a process
chsh - change shell
env - environmental variable
lscpu - cpu information
lshw - hardware information