Help authoring tool to quickly create online manuals, help files, user guides and documentation.
Cross-platform CHM reader and Markdown authoring tool
A free software to view CHM (Compiled HTML Help) format files.
HelpXplain - Simply tell it with pictures
HelpNDoc is a help authoring tool which can produce HTML web-sites, CHM help files, PDF and Word documents, iPhone web-sites, ePub and Kindle eBooks as well as QtHelp files from a single source.