Fountain is a simple markup syntax for writing, editing and sharing screenplays in plain, human-readable text. Fountain allows you to work on your screenplay anywhere, on any computer or tablet, using any software that edits text files.
Fountain supports everything a screenwriter is likely to need in the early, creative phases of writing. Not included are production features such as MOREs, CONTINUEDs, revision marks, locked pages, or colored pages.
Because it’s just text, Fountain is also a great format for archiving screenplays without worry of file-format obsolescence or incompatibility.
Link: Check out Fountain