Screenplay Writing Software

What is the best software available for helping you write a script (screenplay) and where can I get it?

I'm trying to put my screenplay together, never written one professionally but I plan on getting into the business.

Public Comments

1. Microsoft Word.
2. Final Draft is one of the industry standard packages. It costs, but I think you can trial it if you go to their website.
3. I recommend Final Draft but it costs you money You can get free screenplay software called Cinergy script editor here's the link http://www.mindstarprods.com/cinergy/scripteditor.html