If you're in the scriptwriting industry, Final Draft is widely considered as one of the finest screenwriting tools available. It is very expensive however and Celtx tries to offer a free alternative.
However, it comes at a cost and it is specifically tailored to screenwriting and none of the production stages that follow it. Celtx, however, tries to cover both areas, in a software package that combines what it calls 'full-feature scriptwriting with media rich pre-production support'. It's also ideal for those that want to collaborate from a distance because it allows you to post and edit online.
Celtx is certainly better than using Word as your script software although it can hardly be compared to Final Draft. However, it is free and that's got to be a big positive for struggling aspiring writers. Celtx helps you in the formatting of your script and breaks it down so it's easier to analyze and edit. Many users have reported the emphasis is on screenwriters rather than playwriters but it could easily be adapted for the needs of the latter.
It's not clear how the collaboration features work however. Celtx is supposed to support online collaboration but there's no clear way of setting this up inviting other users.
Overall, considering it's free, Celtx is an excellent tool for anyone that's disillusioned with Final Draft or is on a shoe string budget.
