Screen sharing is finally a built-in feature in Mac OS X.  Hallelujah!  You’ve long been able to see and have access to the files of other Macs on your local network (with their permission, of course).  Now, Mac OS 10.5 Leopard adds the ability to not only see another Mac, but to take it over completely.

That’s right.  Once your Leopard-based Mac sees another Leopard-based Mac on your network, a Screen Sharing button appears.  Click the button, and, assuming you have the permission of the other Mac, and the other Mac is not asleep, the Screen Sharing application opens, and the other Mac’s screen appears in a window on your Mac.  At that point, you can do anything on that Mac that you could do sitting in front of it using the keyboard and mouse.

But what if you’re not on a local network with the Mac whose screen you want to “hijack”?  Apple has also built screen sharing into iChat.  Simply fire up an iChat session with a Leopard-using buddy.  Select “Ask to Share Remote Screen” from the “Buddies” menu.  Your buddy on the other end can accept or deny your request.  Should they accept, their desktop becomes your desktop.  Your Mac’s desktop fills a small window.  Clicking said window toggles back and forth between the two desktops.

This will be an invaluable feature for professional and amateur computer consultants.  Rather than spending an agonizing amount of time on the phone talking someone through a process on their Mac, you can just begin an iChat session with them, take over, and perform the task for them.  Carried one step further, one could easily provide live tutorials on Mac use, as the video or audio chat is still active during screen sharing.  We’ll talk more about other iChat collaborative features when we cover the application in depth sometime down the road.

Another variant of Leopard screen sharing is called “Back to My Mac”.  Let’s say I am on the road with my MacBook Pro, and either need a file from my iMac at home or need to help the fetching Mrs. Z with a particular task.  Back to My Mac provides screen and file sharing between Macs over the internet.  The Back to My Mac system requires that both Macs be logged in to a .Mac account, which handles the “handshake” between the two Macs to provide a secure connection.