Orthanc is a lightweight self-contained DICOM store, requiring no dependencies or external database. It provides the basic features of a PACS system without extensive configuration. In addition to standard DICOM network functionality, Orthanc provides a REST API to its store, find and move SCP and SCU operations. This provides a language-independent means of scripting operations and employs standard Web technologies such as HTTP transport, JSON format data files and PNG images. A web-based GUI interface is also provided for most functions.