A few basic concepts to find your way around the language used by the industry.
Bythelens is intended for screenwriters. Having said that making movies is a collaborative effort and it's useful to understand a little of the jargon in use by the major departments in a production, if for no other reason than it'll help you understand what everyone's talking about.
This is the part where writing takes place, so it's the most important for the writer. It's also where most of the design, casting and planning takes place. Locations will be scouted, wardrobe put together. It is, in general, mercifully jargonless.
Production - Camera department
Nowadays most movies are shot digitally. Don't worry about distinctions like 4:2:2 or 4k image sensors, they don't affect the way the movie is shot. What you will find is that a lot of people talk about lenses and lights.
Lenses are complex and impressive pieces of engineering but they only really have two numbers that matter to the person using them: Focal length and Aperture. Lenses with longer focal length magnify the scene, allowing you to keep the camera further away from the actor but still have the shot appear to be the same. Lenses with larger aperture let in more light, allowing them to work in dimmer conditions or to gather enough light for the scene more quickly. Lenses with larger apertures are therefore often called fast lenses. Focal length is measured in millimetres. Aperture is measured in something weird called F-stops. The f-stop is actually a ratio between the aperture and the focal length, meaning that longer lenses need to be wider at the front for the same f-stop number (in general). F-stops are measured in a series of square roots of the total area of the aperture, so a lens that's F:1.4 lets in half as much light as one that's F:1.0 but twice as much as one that's F:2.0. You'll often hear people talk in terms of half-stops and third-stops, so someone might assert that changing the shot might cost two-thirds of a stop, for example. As films are told using images and sounds these technical terms make a real difference to the way the finished product tells the story.
Lights are generally divided into categories based on what is fixed in front of the bulb, so Fresnels for example, use a lens to help focus the light. Other than that you will hear terms like snoot (a tube in front of a light that makes it shine a very narrow beam), egg-crate (a deep mesh in front of a light that keeps any from spilling out from the sides, tightening the spot) and barndoors which are adjustable flaps in around the edges of a light to control its beam (you sometimes see similar devices attatched to camera lenses, but in that case they're always used with one side at the top and that top one is called a French flag).
The camera department is run by someone called a Cinematographer, or a Director of Photography, or sometimes a Lighting Cameraman. The person who operates the camera is known as the Camera Operator and on a big set will usually have assistants. The Focus Puller is also known as the First Assistant Camera Operator and is responsible for adjusting the lens during the shot, pulling focus, in fact. The Clapper Loader or Second Assistant Camera Operator loads and manages the film, or digital media, writes up the clapperboard and operates it on set. If the clapper is used at the end of the shot rather than at the beginning (as is more traditional), the clapperboard is held upside-down. The Clapper Loader is not held upside-down because it makes them angry.
If a film needs more than one camera they are usually given a letter code, Camera 'A' and so on. Each camera generally has its own crew.
Production - Sound department
These days people are beginning to expect many movies to be talkies. Sound on set is captured by a Sound Recordist. Usually sound is not recorded on the same bit of media as the pictures (though it can be). When it comes time to match the sound to the picture it would be really useful if you had someone holding up a sign at the beginning of each shot that identified it uniquely for the camera, while also reading out what it said, for the benefit of the microphones. Even more ideal, what if it had, built in, some mechanism for making a sharp noise and being really obvious about when that happened? Then you could match the two parts perfectly. Did you ever wonder what a clapperboard was? Well now you know.
Sound is captured by using microphones and on a film set the most common types are Cardioid, which are somewhat directional, and Hypercardioid, or Shotgun, which are very directional and are used to cut out extraneous sounds. Microphones are often protected using devices that take wind-noise out. These are called Windscreens or, if they're the furry kind, Deadcats. Microphones are sometimes mounted on poles called Booms carried by Boom Operators.
Many scenes are shot on custom built sets, as opposed to on location. These sets are constructed in buildings known as Stages and if they're soundproofed they're called Sound-stages. If picture is being captured but the sound will be recorded at another time there's no need for a quiet set, the industry term for this is MOS.
Production - Grips
The specialist tradesmen who operate the film set are called Grips. The top electrician is called the Gaffer, the overall head of the grip department is called the Key Grip and the deputy electrician is called the Best Boy. The grips often move the camera around, part of which involves building a set of rails for it to run on called Dolly Tracks. The little platform that runs on the tracks to hold the camera and often the camera crew is called a Dolly so the grip who moves it along the rails is called the Dolly Grip. As the description implies, though the name seems indicative of a small individual, the job often requires someone of considerable strength.
Production - Design
Sets are built by the Art Department and then filled with props and furniture by the Set Dressers. Actors are clothed by the Wardrobe Department, led by someone generally called a Wardrobe Mistress.
Post-production is mainly about Editing and, unsurprisingly, the Editor runs the show. There are specific roles in Sound Editing, Effects Editing and even Titling and Credits Design.