An MLT file is a project file created by Shotcut and other video editing software built on top of the MLT Multimedia Framework, an open-source multimedia authoring framework designed for television broadcasting. The file itself does not contain actual video, audio, or image media. Instead, it is saved in an XML-based plain text format that stores all the instructions, timeline metadata, clip references, transition points, audio levels, and effects applied to a video project. Because it is a text-based project file, its file size is generally very small compared to the rendered output video. When a user opens an MLT file, the video editor reads the XML structure, locates the referenced media files on the local hard drive, and reconstructs the timeline for editing or final export. It allows non-destructive editing, meaning the original source footage remains completely unaltered throughout the creative process.