OTB === **Orfeo ToolBox (OTB)** is an open-source project for state-of-the-art remote sensing. Built upon the foundation of the open-source geospatial community, it can process high-resolution optical, multispectral and radar images on the terabyte scale. A wide variety of applications are available, such as ortho-rectification, pansharpening, classification and synthetic-aperture radar (SAR) processing. **OTB** is equipped with more than 100 ready-to-use applications for remote sensing tasks. They usually expose existing processing functions from the underlying **C++ library**, or integrate them into high-level pipelines. **OTB applications** allow the user to: - combine two or more functions from the OTB; and - provide a high-level interface to handle input and output data, definition of parameters and communication with the user. For a complete list of applications, see `All applications `__. All standard applications share the same implementation and automatically expose generated interfaces. However, they are accessed in a slightly different way (the command-line interface is prefixed by :code:`otbcli\_`).