Screen Sharing is a VNCclient by Apple Inc. included as part of Mac OS X v10.5. It allows remote observance or control of any Macintosh machine on the local network that has Screen Sharing activated. It may also be used over the Internet via iChat. Because Screen Sharing is a VNC client, it may also be used to control any computer running a VNC server if the IP address of the target computer is known and accessible. Apple's Back to My Mac feature of MobileMe service offers Wide-Area Bonjour to allow Screen Sharing and File Sharing access beyond LAN.