Dropbox is a file hosting service operated by American company Dropbox, Inc., headquartered in San Francisco, California, that offers cloud storage, file synchronization, personal cloud, and client software. Dropbox allows users to create a special folder on their computers, which Dropbox then synchronizes so that it appears to be the same folder (with the same contents) regardless of which device is used to view it. Files placed in this folder are also accessible via the Dropbox website and mobile apps. Dropbox uses a freemium business model, wherein users are offered a free account with a set storage size and paid subscriptions for accounts with more capacity.