What to learn: Bootstrap 3 or Bootstrap 4?

Question

Bootstrap

The fourth bootstrap has already been released. Bottom line: what to teach a beginner in web development first? Bootstrap 3, and then finish learning the 4th, or immediately learn the fourth? And tell me, if you can, any resources on the 4th or 3rd bootstrap.

Answer 1

Both. The third one is entirely on Float. Fourth on Flexbox. You are forced to learn both if you want to understand someone else's code, because float will not soon cease to be relevant with its impurities from styles in HTML code, among content where this by nature should not be at all, according to the original idea of ​​cascading style sheets, and if you come across something similar in someone else's code, then you must certainly understand why it was created at all in order to develop faster, it is also important to know the background regarding this particular case.
And it has not yet come out, learn English better first of all, because the official website says Currently 3.3.7 and 4 is comming , do not mislead yourself and other people.
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