The difference between the 400 and 404 HTTP errors

Question

What the difference between the 400 and 404 HTTP errors?
Can you show me an example for understand the difference?

Thank you.

Answer 1

The 404 represent resource not exist. i.e The called API dose not exist or Request Page dose not exist. But in case 400 the resource exist but input is wrong.

404
http://example.com/pageNotExist.html


400
http://example.com/Api/getCustomer/email@xyz.com
//here email is wrong or not exist