In web development, crafting a web page is not just about writing HTML$,$ CSS$,$ and perhaps some JavaScript code. A robust, functional, and user$-$friendly web page results from a multi$-$step process that involves coding, testing, and validation. Each component serves a distinct purpose and contributes to a web page's quality and reliability. Build your initial post on your response to the following questions:

Coding:

What role does responsive design play in coding a web page?

Validation

What tools and techniques are available for validating a web page's HTML$,$ CSS$,$ and JavaScript?