Cross-platform software for keeping your notes in a tree
OutWiker is a cross-platform software for keeping your notes in a tree.
Similar programs call "outliner", "tree-like editor" or personal wiki.
Main difference OutWiker from other programs is a keeping notes as folders on disk.
A notes can to have attached files. OutWiker can contain pages of different types,
currently supports three types of pages: plain text, HTML pages and wiki pages.