With its ability to let users "travel back in time" to find deleted files, applications, photos or other digital media, Time Machine automatically backs up everything on the Mac to an external hard drive or Mac OS X Server. In the event a file is lost, users can search back through time using a time-based visual display to find and then instantly restore the file. With one click, Time Machine can restore anything from a single file or photo to everything on a Mac.

Spaces is a new way to group applications required for a given task into a "space," then switch between different spaces to bring up the specific applications required for that given task. Users can get a bird’s eye view of all their Spaces and choose where they want to go next with just one keystroke or click of a mouse.

With Leopard. iChat is designed to make video chats more fun with the ability to use Photo Booth effects and put images and videos in the background. iChat Screen Sharing enables users to share their desktops with others to work together in real time on an activity. With iChat Theater, users can share an iPhoto slide show, a QuickTime movie or a Keynote presentation within an iChat window.

Leopard’s Mail includes more than 30 customizable stationery designs to create emails enriched with beautiful photos and graphics. Templates include photo collections, invitations, birthday cards and other greetings. With Mail Notes, users can quickly jot down thoughts and ideas, add graphics and attachments and use the familiar Mail application to manage them like an email message. In addition, To Dos can be created from any email message or note and viewed in iCal or sent to friends and colleagues. RSS news feeds now appear in Mail, allowing users to receive news in their inboxes, receive notifications when new stories appear and use Smart Mailboxes to organize news about the same topic in one place.

Additional features in Leopard include:

° Full native 64-bit support that allows applications to take complete advantage of 64-bit processing while maintaining full performance and compatibility for existing 32-bit Mac OS X applications and drivers;

° Enhancements to Boot Camp, Apple’s technology that was previewed as a public beta in April and which lets you run Windows natively on Intel-based Macs;

° Front Row, now available with all new Macs to play back digital content, including video Podcasts using the Apple remote;

° Photo Booth, Apple’s f application that lets users take quick snapshots with an iSight video camera, add visual effects with the touch of a button, and share them via email;

° iCal 3 with group calendaring capabilities, event drop box, and standards-based CalDAV support;

° Improved Spotlight searching that’s faster, provides richer previews, and lets users search across network mounted folders on other machines;

° A new Movies Dashboard widget for movie times and Web Clip for clipping any part of a web page as a live widget;

° New parental controls including curfews, time limits and remote administration;

° Core Animation, a new graphics technology that lets you create visual effects and animations;

° Enhancements in Universal Access, including improvements in VoiceOver, Apple’s built-in screen reader;

° Security enhancements including anti-phishing protection in Mail and Safari, and an automatic firewall that limits network resources available to an application; and

° New development tools, including Xcode 3 with full 64-bit support, DashCode, a way to create new Dashboard widgets without writingcode, and Xray, for optimizing application performance.

"Breakthrough features like Time Machine and Spaces are good examples of how Mac OS X leads the industry in operating system innovation," Jobs says. "While Microsoft tries to copy the version of OS X we shipped a few years ago, we’re leaping ahead again with Leopard."

Pricing and exact availability haven't been announced.