-someone who writes screenplays
-Screenwriters or scenarists or scriptwriters are people in a film crew who write/create the screenplays from which films and television programs are made.
-Screenwriting is the art and craft of writing scripts for film, television or video games.
-A writer who either adapts an existing work for production as a movie, or creates a new screenplay.
In the film industry, screenwriters are now recognized as being
just as important as directors in making films. The cliche still holds
true, you can make a bad movie with a good screenplay, but you can't
make a good movie with a bad screenplay.
Script revision is often a free-for-all because during the movie-making
process, anyone and everyone feels they can add to or subtract from the
script, leaving the screenwriter little control over his or her own
work.
Here's a Video from tv lesson website discussing about The Importance of Screenwriter
http://www.tvlesson.com/video/46048_the-importance-of-screenwriting-16.html
And here's a good article on How To Become A Screenwriter
http://filmtvcareers.about.com/od/gettingthejob/a/HT_Screenwriter.htm
