The HTML page begins with an explanation of what HTML is and how to code using HTML. The website does so by providing tutorials and functioning code snippets that can be used by beginners or topics used by advanced developers such as embedding multimedia files. The website also provides a place to test your code, use key resources, reference material, learn hacks and much more.
The CSS page opens with an explanation of CSS and how to code using CSS. The layout is consistent with the layout of HTML page, listing key resources, references, demos, methods for styling text as well as a CSS layout cookbook. The cookbook is an excellent CSS development tool for ideas and useable code to aid in the web development process.
In conclusion, MDN is one of the most important resources available to web developers. It contains massive amounts of information and code to aid developers at all levels. Both websites are easy to understand, have a simple layout, easy to navigate and user friendly. There are no visual distractions on either website, just well-organized references and resources that can be applied by all developers. I would recommend MDN as a resource.