Azure Blob Storage is not a hierarchical file system and does not use directories (folders) to organize files. Files and data are stored in a Binary Large Object (BLOB or blob) but are presented in the illusion of a hierarchical file system.

This becomes most apparent when creating, syncing, or uploading an empty folder to Azure Blob Storage.

Azure Blob Storage will represent an empty folder as a zero-byte file of the same name.

Azure will manage these zero-byte files, and their corresponding empty folders, itself. However these zero-byte files may present themselves to other programs, applications, and services that use the Azure Blob. They should be considered a "normal" side effect of using Blob storage.

Files.com follows the same conventions used by other software to emulate folders on these non-hierarchical file systems. We aim to interoperate using as many reasonable conventions, standards, and best practices, as possible.