Opera Software has released its fourth beta version of Opera 5.0 for Mac OS X.

This version introduces new features, including QuickTime support and support for scroll-wheel mice. The beta is available for download from the company. Also available is Opera 5.0 for Mac OS 7.5.3 to 9.2.x.

Opera includes features such as a cookie manager, hotlist and multiple download monitor. It also supports Apple's Keychain password security feature. It's widely regarded as one of the fastest available browsers. Its features, such as a single button control for toggling images off and on to preserve bandwidth when searching the Web, are "easy to use and access", Opera claims. Opera lets users decide whether or not to save any open browser windows for the next session when Opera is turned off. It also lets its users zoom in on a page by up to 1,000 per cent.

Opera is available in ads sponsored and ads-free versions - the ad-free version costs $39.

Opera supports most prevalent Web standards, including: 128-bit encryption, TLS 1.0, SSL 2 and 3, CSS1 and partial CSS2, XML, HTML 4.01, HTTP 1.1, ECMAScript, JavaScript 1.3, WAP/WML and partial support for DOM.