credibility vs credulity

How is “credibility” different from “credulity” and how do you use these words?
thanks in advance.

the quality that somebody/something has that makes people believe or trust them
to gain/lack/lose credibility
The prosecution did its best to undermine the credibility of the witness.
After the recent scandal, the government has lost all credibility.
Newspapers were talking of a credibility gap between what he said and what he did.

[uncountable] (formal)
the ability or willingness to believe that something is real or true
The plot of the novel stretches credulity to the limit (= it is almost impossible to believe).

Credibility is believability or trustworthiness and quality of reputation. Credulity is naivete.

The man’s account simply lacked credibility, so the jury is expected to return a guilty verdict.

The company enjoys the greatest credibility in the computer market. Customers have grown accustomed to its reliable, feature-rich machines and quality troubleshooting.

You have learned from your mistakes. I’m sure it was just the credulity of youth. There is no need to worry going forward.