Mar 4, 2011 12:37 GMT  ·  By

With Mac OS X Lion, Apple claims to be taking its best thinking from iPad and bringing it to the Mac. The revolutionary desktop OS will be available this summer.

We like to treat our readers to one new feature at a time, in the form of short previews (like this article here) before the software is released to the general population.

This time we’d like to take a look at Versions.

Touted by Apple as a feature that allows you to “see every step you take,” Versions works with specific apps that are designed to take advantage of the feature to make a snapshot of the document in time, rather than a separate file.

“Versions records the evolution of a document as you create it,” Apple explains.

“Mac OS X Lion automatically creates a version of the document each time you open it and every hour while you’re working on it.”

At some point, you may want to undo a boo boo, or completely retrieve a portion of a document long after you’ve started working on it.

You can do so via a very familiar interface.

Versions shows you the current document next to a cascade of previous iterations, whenever you need to revert to an older instance of a file, or retrieve part of a document.

This is done in an interface similar to that of Time Machine, allowing users to see how their work looked at an hour ago, two hours ago, and so on.

Versions only saves the changes to the document, which avoids duplication of the data that hasn't changed, just like to Time Machine does with its multilink backups.

From here, users can revert with a single click, or copy and paste work from a previous state into the current version with familiar commands.

A picture depicting Versions at work is displayed above (a promotional material by Apple using one of the new MacBook Air computers). Click to enlarge the image.

For more coverage of the key features making up Lion, hit up the related links.