Regex excluding specific characters

Question

In this lesson I don\'t understand why [^b] is not correct? I understand that [^bog] is correct.

[^b] should match any string

Answer 1

[^b] will only match one character that is not 'b'.
[^b]+ will specify that RegEx group to match one or more characters that are not 'b'.
[^b]* will specify that RegEx group to match zero or more characters that are not 'b'.