Most computers and monitors are natively set to 60Hz which is fine, but gaming can be so much better with more Hz.
With higher refresh rate on your screen means your game can run at the true FPS it was capable of. Running a game 200FPS to a 60Hz monitor is a great shame, and would likely lead to 'tearing' where your graphics miss-sync with the Hz of the display.
Enter the world of Hz and FPS...
If you have a powerful enough computer you can match your gameplay FPS to your monitor Hz, if you have a decent monitor as well.
Here is a bit of a checklist you need to go 144hz:
All those should enable you to get up and running with buttery frames.