Well, before we jump deeper into the application, please let me quote the definition of Markdown taken from Wikipedia:

Markdown is a lightweight markup language, originally created by John Gruber and Aaron Swartz allowing people "to write using an easy-to-read, easy-to-write plain text format, then convert it to structurally valid XHTML (or HTML)". The language takes many cues from existing conventions for marking up plain text in email.

Just like another markup languages, we can create Markdown with ordinary text editor such as Gedit or Kate. But Uberwriter gives you some advantages when writing or editing Markdown markup language.