Recently, CSS Grid has landed for all modern browsers (as per CanIUse:Feature CSS Grid). This isn't anything thats come out of the blue, but it is impressive that it has landing in most browsers in a similar timeframe.
Recently, Rachel Andrew gave a great talk on the topic which was uploaded to youtube. This was a great introduction to the subject for me, and also provides a brief comparison between CSS Grid and CSS FlexBox.
From this presentation, and this excellently designed tutorial game on using CSS Grid (Grid Garden), I have made my own little CodePen (below) trying out CSS Grid myself.
If you haven't started playing with CSS Grid yet, start now! This is a complete game changer in the world of Web Design and Development.