"a ~350 page book on TeX, plain TeX, and Eplain, originally written by Paul Abrahams, Kathryn Hargreaves, and Karl Berry. It is now a free GNU package ... [a] prebuilt PDF file is available" (ib., 2019-11-10)
"Documents can be saved in TeXmacs, Xml or Scheme format and printed as Pdf or Postscript files. Converters exist for TeX/LaTeX and Html/Mathml. Notice that TeXmacs is not based on TeX/LaTeX." (ib., 2019-10-14)
"Tool to help turn minimally marked-up plain text into well formatted documents, including HTML, PDF (by way of LaTeX), OPML, or OpenDocument (specifically, Flat OpenDocument or ‘.fodt’ (...) MMD is a superset of the Markdown syntax, originally created by John Gruber. It adds multiple syntax features (tables, footnotes, and citations, to name a few)" (ib., 2016-12-03)
"a drop-in replacement for the original AsciiDoc Python processor (...) Asciidoctor recognizes additional markup and formatting options, such as font-based icons (e.g., icon:fire) and UI elements (e.g., button:[Save]). Asciidoctor also offers a modern, responsive theme based on Foundation to style the HTML5 output."
"a text document format for writing notes, documentation, articles, books, ebooks, slideshows, web pages, man pages and blogs. AsciiDoc files can be translated to many formats including HTML, PDF, EPUB, man page."
"real-time collaborative environment for LaTeX built in nodejs. It includes a beautiful LaTeX ACE Editor and a PDF renderer." "It's a free and open-source version of ShareLatex." Unfortunately, development stopped end of 2014.