Help and reference files

• www.w3schools.com: Free tutorials on (X)HTML, JS, CSS, PHP, and a lot of other Web master resources
• www.freeprogrammingresources.com: Free tutorials on various programming languages and operating systems
• www.programmersheaven.com: Programming tutorials
• TechHelp: Advanced tutorial on DOS & BIOS
• fdd5-25.net: A site about downgrade, an interesting computer-related perspective with downloads of ancient software (Russian; the Google translation is quite readable though)