Screenplay format

In class we have learnt about how to format screenplays, a professional  screenwriter came into class and taught the class the basics, from this I have learnt:


Slug line- The tag which goes at the beginning of every scene, it contains the location, interior or exterior, and the time of day. (INT. PLAYGROUND. DAY)


Action/description- The line that describes what happens in the scene, excluding dialogue, and the character's looks/actions. (STEVE SMITH opens the door to reveal JOHN DEAN behind in a long velvet gown)


Speech- When a character speaks it is formatted so the name is central and the dialogue starts on the next line, this can also include bracketed directions into how the lines should be said or portrayed.


                                                                           STEVE
                                                                         (frustrated)
                                            What are you doing here at this time in the morning?


Transition- At the end of scenes you can include transitions to indicate to the reader/director how to end the shot, however these are only optional. They appear at the far right of the page like this:
                                                                                                                                        DISSOLVE TO:


He also added that if it does not use the courier 12pt font most people will not consider investing or adapting the screenplay.