If you are into tweaking your WordPress Theme or designing one from scratch, here are some HTML/XHTML and CSS Cheat Sheets you might want to add to your resources.

HTML/XHTML Cheat Sheets

• HTML Cheat Sheet
• HTML Tags Cheat Sheet
• HTML Tag and Code Cheat Sheet
• The HTML Source - HTML Cheat Sheet
• Web Monkey - HTML Cheat Sheet
• CDBurnerXP - HTML Cheat Sheet in PDF format
• A Simple Guide to HTML - HTML Cheat Sheet
• HTML Tag Cheat Sheet
• fcXHTML Reference

CSS Cheat Sheets

• CSS Cheat Sheet
• Cascading Style Sheet Cheat Sheet
• Apple’s CSS Cheat Sheet
• Tek271’s CSS Cheat Sheet
• CSSREF
• SeeSS

WordPress Cheat Sheets

• Official WordPress Theme Architecture Outline and Cheat Sheet
• WordPress Plugin API Cheat Sheet
• WordPress Theme Cheat Sheet
• WordPress Cheat Sheet by Andy Wibbels
• HeadZoo WordPress Plugin API Cheatsheet
• HeadZoo WordPress Themes Cheatsheet
• Diary of a Rock Star - WordPress Cheat Sheet
• Kahi’s WordPress Notes - WordPress Cheat Sheets Summarized

1. Administration pages and options hierarchy by Andy Wibbels
   • download as PDF
   • see preview thumbnail
   • article about
2. Wordpress database structure by unknown author
   • download as PNG
   • see preview thumbnail
3. The Loop with it's template tags (plus some another) by Bueltge.de
   • download as PDF
   • see preview thumbnail
   • article about
4. Widget frame (A widget-file example, code commented in German) by Bueltge.de
   • download as PDF
   • see preview thumbnail
5. Plugin API (Action- and filter-hooks, some function names, plugin-file header) by Bueltge.de
   • download as PDF
   • see preview thumbnail
6. Template tags (categorized template tags, theme header, bloginfo & get_options strings) by Bueltge.de
   • download as PDF
   • see preview thumbnail
7. Plugin API pic (almost identical with Plugin API in PDF by Bueltge.de, but in PNG format (which makes it practically unusable)) by Headzoo.com
   • download as PNG (image!)
   • see preview thumbnail
8. Template tags pic (similar to Plugin API in PDF by Bueltge.de, plus example of The Loop, but again in PNG format) by Headzoo.com
   • download as PNG (image!)
   • see preview thumbnail
9. Teplate tags in plain text (it's only a selection of the most used TT) by Michael Caputo
   • download as TXT (zipped)
   • article about

PHP Cheat Sheets

• Blue Shoes Developer - PHP Cheat Sheet
• PHP Cheat Sheet
• PHP Cheat Sheet
• Regular Expressions Reference Sheet

Databases/SQL Cheat Sheets

• MySQL Cheat Sheet
• Cheat Sheet SQL Redux
• MySQL Cheat Sheet in PDF format
• Techno Challenged - Oracle Cheat Sheet
• Selector Web Sybase Cheat Sheet
• PostgreSQL Cheat Sheet

Character Codes and Character Entities Cheat Sheets

• HTML Character Entities Cheat Sheets
• Web Monkey - Special Characters
• HTML Goodies - So, You Want An ASCII Code, Huh
• ASCII Codex Cheat Sheet
• Character Entity References in HTML 4 and XHTML 1.0
• Digital Media Minute HTML Character Entities Reference Guide
• WordPress Codex - Using Fun Character Entities in WordPress
• ASCII HTML Codes
• Microsoft Developer’s HTML Character Sets
• Chami’s Tips: HTML Special Character Reference
• The Unicode Consortium site
• Digital Web Magazine’s Extended ASCII Characters for HTML
• Browser Support for Extended Characters
• University of Texas - Special and Extended Characters
• HTML Accent Entity Codes

Search Engine Cheat Sheets

• Google - Advanced Operators Reference Guide
• Google Help Cheat Sheet
• Web Search Engines Cheat Sheet
• Search Engine Cheat Sheet

ReWrite and htaccess Cheat Sheets

• Mod_rewrite Cheat Sheet
• The htaccess Cheat Sheet
• A htaccess Cheat Sheet
• Windows Cheat Sheet
• Rain Unix Cheat Sheet
• Pixel Beat Unix Cheat Sheet

Code Paste Bins - Sharing Code, Collaborative Debugging Tools

• Pastebin.com
• http://paste.uni.cc
• Pastebin.co.uk

Free Online Tools for Converting HTML to Publishable Text

• Quick Escape Raw HTML to Escape Characters Converter
• WordPress Encode HTML Entities
• HTML Code Converter
• Tamba2’s Simple Code Converter
• HTMLizer Data
• FoxInternet - Keyboard HTML Character Entities Converter

More Cheat Sheets and Web Tools

• Lorem Ipsum - Lipsum Online Free Generator
• Javascript Cheat Sheet
• HTML Goodies - “AND” Commands
• Essential FTP Commands
• Podcasting Cheat Sheet
• RGB Hex Colour Chart
• Cenophobie.com Ruby Cheat Sheet
• Digilife - Quick Reference and many cheat sheets in PDF Format
• Big Bold Snippets
• Apache Cheat Sheet
• Regular Expressions Reference Sheet (PHP)
• Threadeds Ruby on Rails Cheat Sheet
• Rails Tip: What goes where (directory structure) - A cheat sheet
• Ruby Quick Reference and Cheat Sheet
• Cheat Sheet Roundup - Over 30 Cheatsheets for developers

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