javascript - What is the difference between regular expressions written inside square brackets and written outside?

Question

For example, what is the difference between [\s] and \s?

Answer 1

[ab] means or , one of a or b, representing a character set

ab means and , a and b appear at the same time, and ab is continuous.

Answer 2

Do you have to ask this kind of question? Do you understand that Baidu can take 5 minutes?

Answer 3

There is no difference between

[s] and s. They both represent space characters

[abc] As long as one of abc appears
abc must be three consecutive abcs