The ZIP Archive format bundles multiple files using DEFLATE or Store compression with a central directory index, supported natively on every major operating system. Converting to ZST produces a document file that stores data in the ZST format. This extracts the document from the archive so it can be opened directly. Metadata such as creation date and embedded colour profiles is preserved where the target format supports it. This makes ZST the practical choice when the destination system requires it or when the original format is not supported by the target application. 1converter runs this conversion on the server: your file is uploaded encrypted over HTTPS, converted using trusted open-source libraries, and the output is held for 24 hours before automatic deletion.