Tutorial on which this repo is based: Omans Emmanuel: https://medium.com/flexbox-and-grids/how-to-efficiently-master-the-css-grid-in-a-jiffy-585d0c213577
Website being emulated: http://output.jsbin.com/wubudog
Slides: https://docs.google.com/presentation/d/1nPLKlSg5iN2hQudjd9avX8fbu3VfFXtV3hHj_iUgJjU/edit?usp=sharing
It depends. You'll hear as an answer that flexbox is a one-dimensional system and grid is two-dimensional, but that alone doesn't help ME decide which to use. If you know exactly what layout you want on your page, top to bottom and left to right, you can use grid to make it. If you have some content to space along one axis, go ahead and use flexbox.
Firefox Developer Edition Grid Tutorial: https://mozilladevelopers.github.io/playground/css-grid/
List of sites that use grid: https://cssgrid.design/
Rachel Andrew: https://gridbyexample.com/
Rachel Andrew: https://www.smashingmagazine.com/2017/09/css-grid-gotchas-stumbling-blocks/
Jen Simmons: https://labs.jensimmons.com/
CSS-Tricks/Chris Coyier: https://css-tricks.com/snippets/css/complete-guide-grid/