At its annual Worldwide Developers Conference (WWDC), Apple will unveil its next generation software Lion, the eighth major release of Mac OS X, which is the technology giant's desktop and server operating system for Macintosh computers. The latest release is expected to feature many developments made in Apple's iOS, such as an easily-navigable display of installed applications, to the Mac, and will include support for the Mac App Store.

Following are the new features Mac OS X Lion is expected to offer:

Mac App Store

Mac OS X Lion includes the Mac App Store - the best place for users to discover, purchase, and download your apps. Millions of customers in over 90 countries can quickly and easily select from some of the best Mac apps conveniently on their Mac.

Full Screen Apps

Provide an immersive, focused user experience with a full screen app. NSApplication, NSWindow, and the NSWindowDelegate Protocol in Mac OS X Lion make it easy for you to create and manage full-screen user interfaces while providing you the power to design rich user interactions.

Aqua 

Aqua defines the look and feel that users come to expect from Mac OS X. Lion brings it to a new level with popovers, overlay scrollbars, and powerful Multi-Touch gestures and animations.

Popovers 

AppKit framework now includes popovers, a new unit of content that can be positioned relative to other content on the screen. Popovers automatically move whenever the positioning view moves. Users can also design popovers that can be detached, allowing them to become a separate window.

Overlay Scrollbars 

Mac OS X Lion introduces overlay scrollbars similar to those in iOS. These scrollbars appear as an overlay on top of the window's content while the user is scrolling and remain visible briefly to allow scrollbar dragging. 

Multi-Touch Gestures and Animations 

The fluid, responsive animations that create the magical user experience on iPad and iPhone are available in Mac OS X Lion. One can design their apps to use Multi-Touch gestures and animations and redefine the interaction users have with the apps.

AV Foundation

AV Foundation framework provides essential services for working with time-based audiovisual media. Through an Objective-C interface, a user can easily play, examine and compose audiovisual media in his app. An array of powerful classes also make it simple to edit and encode media files. One can even capture audio and video from external devices and manipulate them in realtime.

Auto Save and Versions 

If you have a document-based application, Lion offers an efficient, built-in auto save feature that stores changes to the working document instead of creating additional copies on a disk. Versions automatically records a history of changes made to your documents and lets your app display a Time Machine like interface so users can browse through previous versions.

Resume 

The Resume feature in Lion allows users to restore their apps exactly where they were prior to logging out or restarting. Apps that were last running launch automatically and all open document windows return to where they were. The system automatically manages apps and conserves resources by closing apps that are not being used.

Sandboxing and Privilege Separation 

One can create apps that are more secure with app sandboxing and privilege separation. Sandboxing protects the system by limiting the kinds of things an application can do, such as accessing files on disk or resources over the network. Limiting the capabilities of an app to just those operations that it needs to perform helps keep the rest of the system more secure in the event that an app is compromised. Privilege separation is another common technique for improving security where an app is factored into smaller pieces, each with their own distinct roles and privileges.

File Coordination 

Coordinating access to files between multiple threads and multiple processes can be difficult and error prone. File Coordination helps eliminate inconsistencies due to overlapping reads and writes by allowing your application to access files and directories in a way that is serialized with respect to other processes' accesses of the same files and directories.