Apple released a public beta of its Safari 4 web browser Tuesday that comes loaded with a new JavaScript engine and support for the latest web standards. The Safari 4 Beta is available for download from Apple's Web site; it will set you back about 107MB of disk space.

The Cupertino, California-based firm said that the engine, dubbed “Nitro”, runs JavaScript 4.2 times faster than Safari 3. All in all it is a great update, with several bells and whistles, such as Cover Flow viewing of your history and bookmarks and a swanky pseudo-3D view of your most-frequented websites.

The new Full History search feature can prove to be extremely useful, as it goes through all of the pages you have previously browsed and the text they contain. If you know you saw a certain term somewhere, but you can't remember where, you can simply search for it, and all pages containing it in their body text and name will be displayed.

The browser, which is compatible with Mac OSX and Windows XP SP2 or Vista, supports HTML 5 to allow web-based apps to run offline. It also comes with CSS 3 to enable web graphics using reflections, gradients and precision masks.

Moreover The Smart Search Field in Safari 4 is now integrated with Google Suggest, and one you start typing, the field suggests search strings. This means you'll no longer need Safari plugins, like Inquisitor, to get this kind of functionality.

As far as changes that will be more visible to average users, Safari 4 moves the tabs from below the address bar to the very top of the window, and allows you to add a new tab by clicking a "+" sign in the uppermost right-hand corner of the window.