God.

Also known as the Director of Photography, the DP or the DoP is the main safety net that any sassy producer or studio demands. For it is he who lights the images, who chooses the frame, who makes the girls glitter, and who - after the director - gets to kiss those girls that he got to glitter so very nicely.

So when the film's a complete stinker, at least the stars look swell.

Some cinematographers have hardcore theories about color and light. Others hardly speak. Many like to be hands-on with the camera. Some actually direct the film without the director's knowledge.

All cinematographers enjoy a well-done minced beef patty.

Q: How many directors of photography does it take to change a lightbulb? A: Well ... I kind of like it dark like this.

Most stylish person on the set. A bag lady.

Contrary top popular belief, the costume designer is the not just someone to shop for schmutter. This job is about how the clothes look, how the clothes make the actors feel, how the clothes play against the colors of the set, how the clothes end up in the director's backpack for his wife and kids.

In Hollywood, costume design is all about labels and the cut. In Europe it is about fetching the pleated velvets from the theatrical costumiers. For the rest of us suckers, it is about thrift store shopping on a Costco scale.

Q: How many costume designers does it take to change a lightbulb? A: One. But don't you think it's sexier in black?

A visionary. A fool. A craftsman. An asshole.

The director is the glue of the set. A benevolent dictator, he is the one who channels all the creative juices into place. He develops the script, works with his actors, defines the aesthetic and makes sure it all comes home in one piece.

That's the way it's meant to be, anyway.

Let's face it. At best the director is a great craftsman, a skilled manager of people, an open inquisitive soul and - of course - an artist. At worst, he just turns up. A glorified production assistant? I've heard that more than once.

Q: How many directors does it take to change a lightbulb? A: I don't know ... what do you think?

Anyone who does not work in the film business wants to know two things: what a gaffer is, we'll keep it a mystery!

Keep wondering.

Q: How many union grips does it take to change a lightbulb? A: You're gonna need at least a dozen men. You got a problem with that?

See Production Manager and say the words: "Excuse me, I was just wondering if you knew how beautiful your home is. Have you ever had it captured on film?"

Yvonne. Barry. Lisette. Lionel.

For any aspiring director, the hair and make-up people are the most important people on set. This is because the hair and make-up people are the only ones who know how your stars are feeling.

Think about it. You're a famous movie star, you're about to go on screen, you're worried because your completely past it, and here comes this lovely lad or lady to cover you in Estee Lauder and let the whole world tell you how damn good you look these days.

Why wouldn't you spill your guts?

The money man. The main man. The living embodiment of evil. Hugh Grant's wife.

The producer is the adrenaline of production. It is he who brings the movie into being, manipulating stars, money, ideas, scripts, directors, drugs, studios and the Hollywood Reporter to make it all happen.

Now, no-one really knows what a producer does. And that's why it's the easiest pick-up line in Hollywood. In short, everyone is a producer these days.

Of course, great producers do exist. It is these hallowed souls who fuel the whole movie business, sharing the director's vision and bringing it to the screen with style, panache and publicity.

Aah. Ain't life grand?

Q: How many producers does it take to change a lightbulb? A: One. And you're only changing it the one time.

The first person on set. The last one to leave. The youngest person on set. Everyone's bitch.

The production assistants - also known as PA's or runners - are on the lowest pay level of the feature film experience. They get the coffee. They hold parking spaces in the rain. They lick the road clean with their tongues.

And they love it.

PA's are in lust with the movie business. Their first few months on a shoot are glory days of rose-tinted on-set high-jinx. The next few months are harder, as the reality that they could do everything better slowly sinks in. By the end of a PA's lifespan, they just steal whatever they can get their filthy hands on.

It's a jungle out there.

Q: How many production assistants does it take to change a light bulb. A: Is that with milk and sugar?

The one who's not the cinematographer. The chap over there with the revolving pencil.

The lowly production designer is the least understood person in the whole wide world. All he wants to do is make the shoot look fab, using colors, lines, shapes and textures. All the director can say is: "I don't care Dave. I just need it to look believable as a kitchen."

The production designer creates the spaces where the other stuff happens. If the project is a visual one, the director, production designer and cinematographer form a concrete bond, shaking the very foundations of what the eye can perceive. If the project is not visual, then it's all abut the size of the faucets.

Q: How many production designers does it take to change a lightbulb? A: Hmmm ... does it have to be a lightbulb?

Like a Unit Production Manager. Just smaller.

The grumpy bastard. The happy camper. The fixer. The schmoozer.

The UPM or Line Producer is the office manager of the production process, setting up a universe that the director and 1st AD explode in one big bang. He organizes everything before the shoot, managing a team of sub-managers who in turn delegate and micro-manage and second-guess everything that could potentially go wrong.

The next time you visit a production, you'll recognize the UPM as the bloke with his arms crossed, tapping his foot over by the corner of the set.

Male or female, the UPM always has a beard.

Q: How many UPM's does it take to change a lightbulb? A: Go away.

The actors. The stars. The people who make the film happen. That woman over there with the boob job.

For some reason, people don't call actors "actors". They call them "talent". As in: "Please bring the talent to the set". What is with that? Talent is an abstract term defining skill. It is something one has, not something one is.

And so, one more mystery of film jargon remains unexplained forever.

Q: How much talent does it take to change a light bulb? A: One. But what's my motivation?