What open file format stores Wikipedia content for offline use? ZIM is the answer.
ZIM is an open file format designed to store website content for offline use, especially content from Wikipedia and other Wikimedia projects. A ZIM file can contain articles, images and other auxiliary files, along with full-text search indexes so readers can find information without contacting a live website.
The format is defined by the openZIM project and is closely associated with Kiwix, which reads ZIM archives. This division is useful to remember: ZIM is the container format, while Kiwix is software for opening and browsing the content. The format makes it practical to distribute large knowledge collections for schools, libraries, travelers, and communities with limited connectivity.
ZIM stands for “Zeno IMproved” and replaced the earlier Zeno format. It is not the same as EPUB, which is chiefly an e-book format, or WARC, which is intended for web archiving. ZIM is optimized for compact, searchable offline access to wiki-style collections.