JSDoc - An API documentation generator for JavaScript.
Developerhub.io - All-in-One Platform for Online Documentation
ESDoc - Documentation generator for JavaScript
GitBook - Modern Publishing, Simply taking your books from ideas to finished, polished books.
API Extractor - API Extractor helps you write better TypeScript libraries: It analyzes your exported type signatures and (1) produces an API documentation website, (2) generates a .d.ts "rollup" file, and (3) creates an API report to facilitate PR reviews.
TheDocs - Create beautiful documentation sites. See how beautifully simple your documentation site can be.