MKV is a video format: it stores video, audio, subtitles, and chapters in an open-standard container that supports virtually every codec. FLV is a video format that packages Sorenson Spark or VP6 video in Adobe's Flash container, now largely obsolete following the end of Flash Player support. This conversion changes the file's encoding, compression method, and supported feature set. Metadata such as creation date and embedded colour profiles is preserved where the target format supports it. Converting between these two formats is common when the source application does not support FLV natively or when the target platform only accepts FLV. 1converter processes this conversion server-side using open-source tools. Files are transferred over HTTPS, converted on secure cloud servers, and automatically deleted after 24 hours.