Advanced documentation

Opera is famous for its speed, security, flexibility, and standards support. These documents give you a look behind the user interface, and provide advice for changing files and using advanced settings.

Specifications

Opera prides itself in supporting all major web standards currently in use, including CSS 2.1, XHTML 1.1, HTML 4.01, HTML5, WML 2.0, ECMAScript, DOM 2 and SVG 1.1 tiny.

Opera version history

Captures the history of Opera versions, technology, and major release features.

Changelogs

Administrator’s how-to

Plug-ins and file formats

Documentation

Opera Help

Need help? Hit F1 anytime while using Opera to access our online help files, or go here.