Essential Linux Commands

There are various Linux commands that will make your life easy if you develop a habit of practicing them regularly. I will try to list some of them here and if required, modify the post to include the missed ones.

man: if you are unsure about how to use certain commands, use man (unsure_command). This is a life-savior. Trust me!
pwd: pwd will show you the full path of where you are in the directory.
ls : ls will show you a list of files/directories that are present in your present working directory.
chmod: chmod will let you make changes to your file modes.
chown: using chown, you can change file owner and group.