1877 Thomas Edison invents the phonograph.

1899 At the Edison Company, Laurie Dickson invents the Kinetophone. The first device that plays moving pictures and sound synchronously, it is essentially a Kinetoscope with earphones.

1900 At the 1900 Paris World Exhibition, three different systems for synchronizing phonograph records with projected film strips are exhibited.

1907 French composer Camille Saint-Saëns writes the first original film score. Until the advent of recorded sound in the late 1920s, most feature films shipped to exhibitors contain a musical score for adaptation by a pianist, organist, or, in certain theaters, an orchestra; in some cases, scripts are also provided for narrators.

Lee DeForest perfects the Audion vacuum tube, allowing sound to be magnified and reproduced through speakers for large movie audiences.

1910 Eugène Augustin Lauste invents the first practical sound-on-film system.

1919 Josef Engl, Joseph Massole, and Hans Vogt patent the Tri-Ergon process for recording sound on film.

1923 Lee DeForest patents Phonofilm, a process similar to Tri-Ergon.

1926 Warner Bros. buys exclusive rights to Vitaphone, the Fox Film Corporation introduces Movietone, and RCA introduces Photophone.

The first sound film projected for a public audience is Alan Crosland's Don Juan. There is no speaking in it.

1927 Alan Crosland's The Jazz Singer is the first movie to use synchronized sound as a means of storytelling.

The film industry begins the massive conversion of its production facilities to sound, a process completed by 1929.

1928 Bryan Foy's Lights of New York is advertised as the first "100 percent all-talkie."

1929 In Alfred Hitchcock's Blackmail, the first British "talkie," the audience is put aurally in the point of view of the main character. When the word knife is distorted in the character's mind, it is also distorted in the sound track

Postsynchronization is first used in King Vidor's all-black musical, Hallelujah. Other innovative sound films include Rouben Mamoulian's Applause (1929), Lewis Milestone's All Quiet on the Western Front (1930), and G. W. Pabst's Westfront 1918 (1930). Walt Disney introduces the animated musical with The Skeleton Dance (1929).

1930s Jack Foley, a sound technician at Universal Studios, becomes the first "Foley artist," simulating sound effects using various props. These effects are added to films in postproduction.

1932 Rouben Mamoulian's Love Me Tonight is one of the first films to use sound creatively. A montage of everyday noises in a Parisian neighborhood is orchestrated to create an almost musical rhythm.

1940 John Ford's The Grapes of Wrath uses ambient sound to create mood, as when the sound of wind helps convey a character's loneliness and isolation.

1941 Orson Welles adapts many radio recording techniques, and introduces an early equivalent of sound design, in Citizen Kane.

1948 Laurence Olivier's Hamlet uses internal monologue for many of the soliloquies, breaking with theatrical tradition. Sometimes this is mixed with spoken lines, such as in the famous "To be, or not to be" speech, creating a combination of onscreen and offscreen sound.

1951 Stefan Kudelski creates the first Nagra, a portable audio tape recorder with a wind-up motor.

1957 For The Bridge on the River Kwai, David Lean makes a unique choice in having the characters (the British soldiers) whistle their own theme music/score, "The Colonel Bogey March."

1960 Alfred Hitchcock uses an unusual score for his film Psycho; while most Hollywood film scores of the time are fully orchestrated, Psycho employs only a string section, creating an eerie, unsettling mood that would not have been possible with a full orchestra.

1964 In Stanley Kubrick's Dr. Strangelove, or: How I Learned to Stop Worrying and Love the Bomb, the explosion of a nuclear bomb is contrasted ironically with the sound track: Vera Lynn singing the sentimental "We'll Meet Again."

1966 Woody Allen dubs a Japanese spy film to give it a completely new (and humorous) plot for his film What's Up, Tiger Lily?

1968 Unlike many science fiction films and television shows, where space battles are filled with sound effects and dramatic music, Stanley Kubrick's 2001: A Space Odyssey makes frequent use of silence, especially for its outer-space sequences.

1970 Michael Wadleigh uses the Nagra to record live audio at the Woodstock festival for his nonfiction film Woodstock.

1970s Hollywood directors—including George Lucas (THX-1138, 1971), Francis Ford Coppola (The Godfather, 1972), and Robert Altman (Nashville, 1975)—begin mixing multiple channels of sound, each of which can be manipulated individually, laying the groundwork for a new era in what Walter Murch comes to call "sound design," which combines the crafts of sound editing and mixing.

1977 Alain Resnais's Providence uses speech as an outlet for stream of consciousness as opposed to purely dialogue. The audience learns much about the main character through what he says in his sleep.

1979 Francis Ford Coppola's Apocalypse Now uses hundreds of layered audio tracks to create its sound track. In the helicopter sequence, 140 tracks are used. For the first time in movie history, Walter Murch receives credit for "sound design."

1980 Stanley Kubrick plays with the physical characteristics of sound in The Shining to achieve different emotional effects. Changing the pitch of a scene from low to high, as in the "all work and no play" scene, gives the impression of growing apprehension. Similarly, the use of increasingly exaggerated volume elevates tension.

Martin Scorsese's Raging Bull extensively uses Foley sounds—beef being punched and cut, animal noises—for its boxing matches.

1982 Lucasfilm develops the THX sound system.

1992 Robert Altman's The Player uses sound to attract the audience's attention. In one scene at a restaurant, the camera zooms from one table (where the audience has been watching and listening to a conversation) to another one. During the zoom, the volume of the first conversation goes down while the volume of the dialogue at the second table increases. 2001 Steven Spielberg says the breakthroughs in sound beginning in the 1970s have been the movie industry's most important technical and creative innovations to date.