The following was compiled specifically for the Clark College HTML Fundamentals Class but can be useful to WordPress and web design in general.
The following are helpful HTML and CSS references and resources.
W3C Guidelines and Standards
- CSS current work & how to participate
- CSS Flexible Box Layout Module
- CSS3 Template Layout Module – W3C
Basic HTML and CSS Resources and References
- Basic Structure of a Web Page » HTML Elements| Learn HTML – Tags – Tutorials – HTML Cheat Sheet
- CSS Reference | Mozilla Developer Network
- The Shapes of CSS – CSS Tricks
- CSS Structure and Rules
- Terminology, Syntax, & Introduction – A Beginner’s Guide to HTML & CSS
- CSS Examples – Sitepoint
- CSS Portal – Templates, Tutorials, Books, Software, Code Examples
- CSS layouts – Max Design
- CSS Layouts: 40+ Tutorials, Tips, Demos and Best Practices – Noupe
- Selectors Level 3 – W3C
- Why Percentage-Based Designs Don’t Work in Every Browser
- Tips, Tricks and Best Practices for Responsive Design – Webmonkey
- Conversation With X/HTML 5 Team
- An Inside View of the CSS Working Group at W3C
A framework is literally a frame upon which a web designer adds the design elements. A WordPress Theme frameworks is a skeletal frame set with HTML and CSS with all the WordPress code embedded within it, upon which a designer can paint the website walls. 
Learning from Lorelle 