What is the difference between flexbox, css grid and bootstrap 4 and what to use?

Question

css

I basically understand that bootstrap is a framework, a whole combine, and flexbox and css grid are like grid modules and bootstrap 4 seems to use the flexbox grid, but what to use for layout? I'm more inclined towards flexbox, I don't see the point in all the bootstrap functions, please advise how to proceed, what to study?

Answer 1

CSS Grid is too early to use. Get started with Flexbox.
https://caniuse.com/#search=flexbox
https://caniuse.com/#search=grid

Answer 2

Bootstrap can be customized, that is, you can choose what you need for each project.
https://getbootstrap.com/docs/3.3/customize/
Don't let the user download something that won't be used.
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I personally use flexbox, but they are widely used now, I haven’t heard much about grids at all to use them now.