Zuunote - A web-based and Markdown-based note-taking app that's reimagining writing experience in Markdown that everyone can enjoy.
Dr.Explain - Dr.Explain software is a help file authoring tool.
Typora - A minimal Markdown reading & writing app.
Document360 - Self-service knowledge base software focused on SaaS Products & Enterprise Software Projects.
Obsidian.md - A second brain, for you, forever. Obsidian is a powerful knowledge base that works on top of a local folder of plain text Markdown files.
WinCHM - Creating CHM file, Make CHM file, Web Help. WinCHM Pro - Help authoring software (CHM, WebHelp, DOC, PDF) . With this powerful tool you can not only create chm file from scratch, but also convert a set of existing HTML files to a chm file.