Work Folders is a feature in Windows Server 2012 R2 that allows Windows users to store and access work files on personal PCs and Windows devices as well as corporate PCs.
According to Microsoft, Work Folders addresses the bring-your-own device (BYOD) movement by allowing end users to store work files and access them from anywhere. When an end user saves a file, the feature automatically replicates the file to data center servers before replicating the file on the end user's other devices. Following this replication, the saved data can be accessed from any of the user's Windows devices.
Work Folders allows the end user's IT department to maintain control over corporate data by storing the files on centrally managed file servers. Administrators also have the option of specifying user device policies such as encryption and lock screen passwords. Work Folders can be deployed alongside existing deployments of Folder Redirection, Offline Files and home folders.