Although artistic greatness is difficult to measure and categorize, and the process of selection is extremely subjective, these films have been chosen as "Greatest" for one or more of the following criteria:

These are films that have broken technological ground, and contributed to the medium of film in a significant, unique way. They are film milestones that have had an undeniable influence (both positive and negative) on altering or advancing the development of cinema and the film industry in its first 100 years -- with their historical relevance or significance, lasting importance, innovation, experimentation, or landmark revolutionary achievement:

D. W. Griffith's The Birth of a Nation (1915)
Orson Welles' Citizen Kane (1941)
F. W. Murnau's Sunrise (1927)
Disney's Snow White and the Seven Dwarfs (1937) and Fantasia (1940)
Arthur Penn's Bonnie And Clyde (1967)
Dennis Hopper's Easy Rider (1969)
Sam Peckinpah's The Wild Bunch (1969)

These are films that have special qualities or elements of excellence and brilliance, and have mastered the 'language of film' - in noteworthy acting performances, directing, producing, cinematography, script (dialogues or monologues) or story writing, editing, costumes, sound and scoring, special effects, or production design. All elements have been seamlessly blended together to create a critically-acclaimed "great film":

On the Waterfront (1954)
His Girl Friday (1940)
All About Eve (1950)
Raging Bull (1980)
Singin' in the Rain (1952)
A Streetcar Named Desire (1951)
To Kill A Mockingbird (1962)
Mr. Smith Goes to Washington (1939)
Star Wars (1977)

These are films that have won major recognition with film nominations, awards and other honors from annual film award organizations (e.g. The Academy of Motion Picture Arts and Sciences, The New York Film Critics, the National Board of Review, or the Golden Globes):

Gone With the Wind (1939)
Ben-Hur (1959)
It Happened One Night (1934)
One Flew Over the Cuckoo's Nest (1975)
Who's Afraid of Virginia Woolf? (1966)

These are films that have a legendary, widespread, satisfying, never-fading, enduring, entertaining appeal, with authentic emotion and a universality of message (that transcends time and place) to audiences (both internationally and locally), no matter how old the film - these are the genuine "classics":

Casablanca (1942)
It's A Wonderful Life (1946)
The Wizard of Oz (1939)
The Grapes of Wrath (1940)
The Godfather (1972)
King Kong (1933)

These are films that demand multiple and repeated viewings, and when intelligently and critically (re)viewed, provide hidden meanings, new psychological truths, great visual moments, mythic resonance, philosophical insight, lyrical beauty, fresh insights into how to view the world, or enlightened understanding:

The Big Sleep (1946)
The Night of the Hunter (1955)
Touch Of Evil (1958)
Psycho (1960)
Vertigo (1958)
Chinatown (1974)
Sunset Boulevard (1950)

These are films that have a distinctive, memorable, or idiosyncratic style that represents the peak of achievement for a screen performer or for a virtuoso director:

The Marx Brothers' A Night at the Opera (1935)
John Ford's The Searchers (1956)
Woody Allen's Annie Hall (1977)
Erich von Stroheim's Greed (1924)
Ernst Lubitsch's Trouble in Paradise (1932)
Preston Sturges' The Lady Eve (1941)
Martin Scorsese's Taxi Driver (1976)
Charlie Chaplin's Modern Times (1936)
Robert Altman's Nashville (1975)
James Whale's Bride of Frankenstein (1935)
Francis Ford Coppola's The Godfather Part II (1974)

These are films that are prototypical or representative - they are the best, original and primary examples within a film genre or sub-genre, and they have been subsequently emulated or influential in subsequent films:

- Wilder's definitive film noir Double Indemnity (1944) or Huston's The Maltese Falcon (1941)
- Ridley Scott's sci-fi cult classic Blade Runner (1982)
- Astaire and Rogers - musical/dance duo in Top Hat (1935)
- Ford's seminal Western film Stagecoach (1939), George Stevens' Shane (1953), and Howard Hawks' Red River (1948)
- the classic comedy Some Like It Hot (1959)
- Hitchcock's suspense-thrillers including the classic gothic romance/thriller Rebecca (1940), Rear Window (1954), and the clever, entertaining and colorful North By Northwest (1959)
- Kubrick's revolutionary visual sci-fi epic 2001: A Space Odyssey (1968) or anti-war black comedy Dr. Strangelove or: (1964)
- the adventure film classic The Adventures of Robin Hood (1938)
- Ophuls' classic tearjerker Letter From an Unknown Woman (1948)
- the quintessential screwball comedy Bringing Up Baby (1938)
- Spielberg's 'first' blockbuster Jaws (1975)