Whenever you have an instance when you don't need screen's display (like you're running a code in the background ) and it doesn't matter screen is off or on.
In Linux systems ,you can easily turn your screen off , and turn it on back easily with a movement of cursor or a key press without entering any password. It's almost like sleep mode but unlike sleep mode you don't have to put password to turn screen on again.
You just have to move the cursor or a key press and tadaa screen gets on as it was before. This actually saves a lot of battery life since you're turning off the screen whenever you're not using it .
To do it , do the following steps Open terminal
Type this command in terminal
xset dpms force offPress enter. And tadaa screen is off now :D
Turn it on back Whenever you need. This way you save a lot of battery :)
