Is JavaScript validation bad?

Question

It has been long time since we have been validating our forms using JavaScript. I am sure this must be the case with most other developers.

Question:

What if the

Answer 1

You should have multiple layers of validation.

Validation on the client Side

This is definitely useful because validation can be done without having to go to the server. Requests get to the server once they are validated - saves some traffic.

Validation on the server side

If javascript is disabled then the server should also incorporate a level of protection - validation in order to disallow erroneous requests.