Because over the years Hollywood has developed as a highly organized business, screenplays fairly swiftly began to take on a format that by the end of the 1930s became quite systematized and that by now can be created with computerized programs such as Final Draft or Movie Magic. Briefly stated, the standard American script is under 120 pages in length, with the guideline being that "one page equals one minute of screen time." Description is kept to a minimum, with very little in way of camera direction since that is the director's job. A script consists of brief description and dialogue and both are written to be a "good read," as they say in Hollywood. The DreamWorks script copy of Shrek (2001), for instance, which is based on the book by William Steig and a script by Ted Elliott, Terry Rossio, Joe Stillman, and Roger S. H. Schulman, describes the Princess on page one as "lovely" and contains no description of Shrek except for the mention of his "large green hand."
Other "regulations" include ones stipulating there be "no photos or graphics" in scripts and that they must be printed on three-holed paper with two metal brats holding the script together. Beginning screenwriters are always told that "Everyone is looking for reasons not to read your script," so violations of these "rules" can lead to a script being tossed or recycled.
While format was becoming more regularized throughout the 1930s and 1940s, it was also becoming the rule that seldom were Hollywood scripts penned by one author from start to finish. Many writers formed lasting script partnerships, as in the case of Wilder and Diamond. Herschel Weingrod and Timothy Harris, for instance, produced a string of hits from Trading Places (1983) and Twins (1988, with William Davies and William Osborne also credited) to Space Jam (1996, with Leo Benvenuti and Steve Rudnick writing as well), working together five days a week for years. Poetry does not lend itself easily to multiple authorship, but there is something about bouncing ideas off one another that works in collaborative screenwriting.
Even Casablanca , instead of being a single-authored work like a novel, short story, or poem, was written through a very complex series of versions and events, by Julius J. and Philip G. Epstein, together with Howard Koch (1902–1995). "Contributions" came from Aeneas MacKenzie and Hal Wallis, "among others," and the script was "adapted" from an unpublished play, "Everybody Comes to Rick's," by Murray Burnett and Joan Alison.
As script instructors everywhere say to students of the craft every day with a smile:
If you are not willing to see your screenplay as a blueprint that may be redone at any time and by one or more other writers, then you should not go into screenwriting at all for nobody ever paid to go into a movie theater to watch a screenplay. It is only part of a long process to make a film.
Therein lies the excitement and the disappointment of this craft that is less than 150 years old and the reason why many writers have been frustrated by their Hollywood experiences.
Because of the complexities of the long road from idea to final film, the Writers Guild of America often becomes an indispensable player. Founded in 1933, the Guild built on similar organizations such as the Dramatists Guild in New York to form a service union that would help negotiate credits and rights for screen-writers. Clearly the goal has always been to elevate the status of screenwriters and the public's and the producers' awareness of their importance. While it is possible to make a film with no script, the point of a business like Hollywood, which involves increasingly larger amounts of money, is that all those involved want to see what the project is about, and so there is a need for scripts as a genesis for all that follows.
The original agreement put forth beginning in 1940 stated that contracts with Guild members must give screen credit to "the one (1), two (2), or at most three (3) writers, or two (2) teams, chiefly responsible for the completed work," and in addition that these designated writers "will be the only writers to receive screen play credit." Often the situation is not so simple, however, and so each year the WGA (www.wga.org) receives over two hundred cases that it arbitrates to determine who receives screen credit. The Guild is a valuable service for its several thousand members and the more than fifty thousand scripts that are registered with it each year.