A producer is someone who is generally the first person to "develop" an idea that will, hopefully, one day become a movie. This can entail purchasing/optioning a book, short story or screenplay and overseeing the adaptation, expansion or re-writing thereof.

The producer also, in some cases, "packages" the project, meaning hiring the director, the writer(s), lead actor(s), and then presenting this package to a financing entity.

He or she will then assist in determining the budget, or lack thereof, and will decide how long the film can afford to shoot for and where. Throughout pre-production, production and post-production, the producer is very instrumental in all major hiring/firing decisions.

He or she is also, in many cases, the liaison between the production crew and the studio, often, in theory, supporting the vision of the director.

Basically, the level of involvement a producer has varies greatly:

-- some producers merely "package" films and are never heard from again (this can result in an "executive producer" credit).

-- others are brought in to oversee the "nuts and bolts" of day-to-day shooting (also known as "line producer") but do not have final say in creative matters.

-- still others are known as "creative" producers and take a very active role in the entire filmmaking process.

There you have it.