[Linux Command] 10 Super Powerful Linux Commands You Should Know

The best one is

1. Saving the file you edited in vim/vi without the required permissions
   
   :w !sudo tee %


2. Traceroute is a nice command but how about a single network diagnostic tool that can combine traceroute with ping? mtr is your command.
   
   mtr efytimes.com

Reference :

10 Super Powerful Linux Commands You Should Know