Zim is a desktop wiki: a graphical text editor for maintaining a collection of wiki pages. Pages contain links to other pages, simple formatting, images and attachments, and are stored in a folder structure like in an outliner. You create a new page simply by linking to one that does not exist yet. Plugins add features such as a task list manager, an equation editor, a tray icon and version control support. Zim is used for notes, journals, meeting notes and task lists on Linux, BSD, Windows and macOS.
Zim is free software under the GPL (version 2). The copyright is held by the lead developer, whose public profile lists the Netherlands; no company or foundation is named. The code is on GitHub, and translations run through Launchpad and Weblate. All data is stored as plain text files with wiki formatting on your own disk, so you can open, back up or synchronise them with any other tool.