HackMD is a real-time collaboration platform designed for creating, sharing, and managing markdown documents. It serves a diverse range of clients including software developers, technical writers, and academic researchers. Operating in the collaborative software market, HackMD offers a freemium business model, where basic features are available for free, and advanced functionalities are accessible through paid subscriptions. The platform integrates seamlessly with GitHub for version control, supports MathJax for scientific formulas, and allows for the creation of UML diagrams. HackMD makes money through subscription fees for premium features and enterprise solutions.

Keywords: real-time collaboration, markdown, GitHub integration, MathJax, UML diagrams, freemium model, technical documentation, academic research, browser extension, team workspace.