What is difference between crypto and bcrypt

Question

These modules are required like that

const crypto = require('crypto');
const bcrypt = require('bcrypt');

I'm very confused in between them. I want to know what is difference between them and when it should be used.

Answer 1

The bcrypt module contains an implementation of the bcrypt password hashing algorithm and nothing else.

The built-in crypto module contains many cryptographic primitives such as hashing, symmetric and asymmetric encryption, key exchange and some more. It doesn't contain an implementation of bcrypt, but there is an implementation of PBKDF2 which has a similar goal (password hashing) but not as good as bcrypt.