Amazon S3 object storage is not a hierarchical file system and does not use directories (folders) to organize files. Files and data are stored in objects but are presented in the illusion of a hierarchical file system.

This becomes most apparent when creating, syncing, or uploading an empty folder to Amazon S3 storage.

Amazon S3 storage will represent an empty folder as a zero-byte object of the same name. The zero-byte object will be presented as a zero-byte file.

Amazon S3 will manage these zero-byte objects, and their corresponding empty folders, itself. However these zero-byte objects may present themselves to other programs, applications, and services that use the S3 bucket. They should be considered a "normal" side effect of using S3 object 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.