File syncing and sharing services are file hosting services which allow users to create special folders on each of their computers or mobile devices, which the service then synchronizes so that it appears to be the same folder regardless of which computer is used to view it.
Files placed in this folder also are typically accessible through a website and mobile apps, and can be easily shared with other users for viewing or collaboration.
Such services have become popular via consumer products such as Dropbox and Google Drive.