OutWiker (current version: 1.8.1) is a cross platform and freeware outliner or notes organizer. It supports plain text, HTML and wiki style notes with various markups.
Start with File—>New (Ctrl+N) and choose one of the aforementioned page types. Either manually or by using the wiki menu or keyboard shortcuts add formatting to your wiki page. The formatting and markup available include bold, italic, horizontal line, font size, preformatted text, code, bullet list, creation and last modified dates, equations (inside {$$}) and others. Wiki pages can be linked to each other as well using page:// – grab a page link by right clicking a page in the tree.
Pages can be tagged and all tags are visible and clickable on the lower left of the program Window.
Files can be attached to a note and an image preview or thumbnail can be inserted inline using Wiki—>Thumbnail (Ctrl+M). The attached files or images can be inserted in a wiki page with a user chosen width. Attached files can be executed or opened from the program using the play icon on the Attachments toolbar.
Pages can be moved and sorted within the tree. Pages can also be bookmarked for easy access when the tree gets larger. OutWiker supports global search of all text and tags and a search page type can be added to the tree to be used as a permanent place holder instead of using the menu or Ctrl+F every time.
The program’s preferences include an autosave setting, default text options and many other appearance settings. One can also set or change keyboard shortcuts for virtually all program features.
OutWiker has a selection of plugins to add features like ‘DataGraph’, ‘Diagrammer’, ‘Table of contents creation for wiki pages’ and ‘Export notes in HTML’. It is portable and available for Windows and Linux systems (ppa:outwiker-team/ppa) with python dependencies.