Definition(en): Markdown was created by John Gruber and Aaron Swartz circa 2004. The purpose of Markdown is to let users write clean text-based documents that do not suffer from the legibility issues of other 'markup' formats. Markdown uses combinations of characters, for example, hashes (pound-sign), asterisks, and combination of square- and rounded- brackets to prefix or suffix parts of text. The symbols provide instructions to an interpreter. A single hash '#' for example, that prefixes a line of text is an instruction to make that line a top-level header in a formatted document. Two hashes '##' is an instruction to render, or output, a secondary header. And so on. Ultimately the result of writing markdown is a document that can be parsed into a well-formed version of other presentation languages such as HTML or XHTML. There is no single specification for Markdown, nor is there a single canonical output. That is, Markdown syntax could be converted into many other file types. Further descriptions of the background of Markdown and a list of Markdown 'flavors' can be found on the Archiveteam Just Solve It File Formats Wiki: http://fileformats.archiveteam.org/wiki/Markdown Wikipedia also provides a thorough description of Markdown and its syntax: https://en.wikipedia.org/wiki/Markdown#Standardization