Screen Writing: Sluglines - INT. and EXT.
INT. is used to state if the following scene is indoors.
EXT. is used to state if the following scene is outdoors.
So if a character leaves the bedroom and goes into the hallway, both will use the slug with (INT.)
If a character leaves the front entrence to go outside, the slugline for the front entrence will be (INT.) while the outside will of course be (EXT.).
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EXT. HOME - DAY
NANCY digs out a flower from the gardan.
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INT. KITCHEN - DAY
DILLIAN pulls out the salad from the fridge.
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When the character is moving within a single scene from INT. to EXT. or EXT. to INT. then you would use (INT./EXT.) or (EXT./INT.) depending on where they are and where they are going. Which (INT./EXT.) or (EXT./INT.) is used for when a character is getting into or getting out of a car, or a phonebooth if you feel dangerous.
When the character is in a vehicle and they are driving or moving faster then walking or running by means of biking, driving, using a boat, then you would state at the end of the slugling as (MOVING) or (DRIVING).
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INT./EXT. MIKE's MINIVAN - DAY
MIKE gets into his car and starts it.
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