ps aux | grep firefox
sudo killall cupsd
sudo apt-get install htop
sudo renice -5 2744 // Give Priority 2744 0 to -5
df -ah
ls -alh /proc // List of all active processes
ls -alh /proc/1 | less
sudo -i // sudo interactive shell session
cat environ
cat statm
ls /
ls /etc // contains all apps configuration files
ls /etc/ssh/ // contains ssh configuration files
ls /sbin | less // regular binaries need for sudo for execution
ls /bin | less // any application installs and shipped binaries
ls -alh /bin | less
ls /bin | grep rmdir
ls /tmp
ls /home // home for users
sudo ls /root
ls /lib64
ls /lib // shared libraries
man hier OR man 7 hier
ls /boot
ls /dev
ls /dev | grep sd // sda sda1 sda2 sda5 -> Disk and Partitions
ls /etc | less
/sbin /ifconfig
ls /usr/bin | less
ls /usr/bin | wc -l
rm -rf /home/newuser