SDLXLIFF is an XML based file format specially developed for use in SDL Trados Studio. It is compliant with version 1.2 of the XLIFF standard. SDLXLIFF stands for SDL XML-based Localization Interchange File Format.
SDLXLIFF files are bilingual files; they contain both the source document text and the translation text.
When you start a new translation in SDL Trados Studio, the content of the source language document is placed in an SDLXLIFF file for translation. The SDLXLIFF file is placed in the same folder as the source language document.