SyncToy is free application from Microsoft that synchronizes files and folders between  locations. The location could be on the same computer or different computers on the same network. SyncToy2.1 is powered by the latest synchronization engine from Microsoft Sync Framework 2.0

Do not confuse with Live Sync , also an application from Microsoft, that synchronizes folders between multiple computers connected to the internet. Live Sync client have be installed on each computers before synchronization can be done. You can read it more on the link above.

SyncToy only required to be installed at the main computers, while other computers at the same network that keep the synchronized folders doesn’t require any installation.

A pair of folders that need to be synchronized has to be setup first. Multiple pairs of folders are allowed, but each pair can consist 2 folders only.

SyncToy also can preview the content of each folders in a pair have, before the folder being synchronized. It comes very handy if you have constantly changed folder that you want the other folders to have exactly same files. Download Synctoy here.