FME
FME (Feature Manipulation Engine) from Safe Software (safe.com) is ETL (Extract Transform Load) software for GIS data. As a desktop application it is one of many proprietary GIS software options, although FME has a focus on data cleansing, transformation, and converting map data between formats, and is less about visualisation or editing. "FME server", and "FME cloud" products also exist, but the desktop software is the well-known flagship product. See also wikipedia:Feature Manipulation Engine
FME is proprietary paid-for software, but is available free for charities and non-profit use if you apply through the Non-Profit Research Grant Program.
OpenStreetMap support
As of 2009, FME supports OSM XML formatted data, allowing conversion to and from this and other GIS data storage formats. See the safe.com OpenStreetMap information "Whatever your needs with OpenStreetMap are, use FME to exchange data between its XML-based data model and hundreds of other formats and applications including: GIS, CAD, databases, spreadsheets and tabular formats, other web-based mapping platforms, and more".
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