What is a theme, anyway?
Conceptually, the theme of a WordPress site is its personality. Differences between themes are intended to make visiting each site built using WordPress a unique experience.
Technically, WordPress themes range from
- a single file (style.css) containing a few CSS rules customizing colors
- to a sophisticated framework of programs written in a variety of languages intended as a base on which other people can build themes.
integrating design’s theme evolution
Thematic, parent of the current theme
- Thematic
- ThemeShaper (home of the Automattic Theme Team)
- Wiki Guide to Thematic
- Visualizing Thematic’s Action Hooks
- Visual guide to Thematic’s box layout
- ThemeShaper’s guide to Child Themes
- How to make a child theme for WordPress: A pictorial introduction for beginners (being kept up to date!)
Clear Line, inspiration for look and feel
Boilerplate: Starkers, a solid foundation
- HTML5 Boilerplate project
- Boilerplate: Starkers blog post
- Boilerplate: Starkers theme in the raw
- Getting Started Using HTML5 Boilerplate
Theme Development
- WordPress: Design and Layout
- Yoast’s Theme Infographic
- WordPress: Site Development
- WordPress: Theme Development
- ThemeLab
- WordPress: Functions File about functions.php
- WordPress: Function Reference
- Know Your Sources, WP’s resource list
- Online PHP manual, absolutely superb
Tools
- WordPress: Validating a Website
- WordPress: Theme Unit Test
- W3C Markup Validation Service
- W3C CSS Validation Service
- Theme Check, also Getting the most from Theme-Check
- DeBogger
- Log Deprecated Notices, great for finding problems in older plugins, too.
- Selenium
- MAMP
- WordPress: Developer Documentation

