bash
bourne-again shell
bg
send to background
cat
concatenate and print
cd
change directory
chgrp
change group ownership
chmod
change access permissions
chown
change file owner and group
chroot
run a command with a different root directory
clear
clear terminal screen
cp
copy one or more files to another location
cron
daemon to execute scheduled commands
crontab
schedule a command to run at a later time
cut
divide a file into several parts
dd
convert and copy a file, write disk headers, boot records
df
display free disk space
dig
DNS lookup
dir
briefly list directory contents
dmesg
print kernel and driver messages
du
estimate file space usage
echo
display message on screen