If you use the numeric keypad a lot, and you got tired from turning on the num lock on every time you restart the computer. The solution is that you need to install numlockx, a tool that enable the keyboard’s Numeric Lock during X11 session initialization.
Installation in ubuntu
sudo apt-get install numlockx
For Fedora/ Centos and RHEL
yum install numlockx -y
– For Slackware check this Link