Film criticism is the analysis and evaluation of films, individually and collectively. In general, this can be divided into journalistic criticism that appears regularly in newspapers, and other popular, mass-media outlets and academic criticism by film scholars that is informed by film theory and published in journals.

Journalistic criticism

Film critics working for newspapers, magazines, broadcast media, and online publications, mainly review new releases. Normally they only see any given film once and have only a day or two to formulate opinions. Despite this, critics have an important impact on films, especially those of certain genres. The popularity of mass-marketed action, horror, and comedy films tend not to be greatly affected by a critic's overall judgment of a film. The plot summary and description of a film that makes up the majority of any film review can have an important impact on whether people decide to see a film. For prestige films with a limited release, such as independent dramas, the influence of reviews is extremely important. Poor reviews will often doom a film to obscurity and financial loss.

Reviews and film marketing

The impact of reviews on a film's box office performance and DVD rentals/sales is a matter of debate. Some claim movie marketing is so intense and well financed that reviewers cannot make an impact against it. However, the failure of some heavily-promoted movies (such as Alexander) that were harshly reviewed, as well as the unexpected success of critically praised independent movies (such as Pulp Fiction) indicates that extreme critical reactions can have considerable influence. Others note positive film reviews have been shown to spark interest in little-known films. Major box-office analysis websites like Box Office Prophets and Box Office Guru regularly factor in general film review opinions in their projections of a film's earnings.

Studios respect the clout of reviewers. There have been several films in which film companies have so little confidence that they refuse to give reviewers an advanced viewing to avoid widespread panning of the film (such as The Avengers). However, this usually backfires as reviewers are wise to the tactic and warn the public that the film may not be worth seeing. Such films often do poorly as a result.

Since so much money is riding on positive reviews, studios often work to woo film critics. Any major release is accompanied by mailings to film critics press kits containing background information, many photos for use in a publication, and often small gifts. Film reviewers who appear on television are given clips from the movie which they may use.

Online film reviews