(covers information from several alternate timelines)
The computer voice was an audio interface program designed to allow computers to express information verbally. Many space-faring cultures, such as the United Federation of Planets, the Romulan Star Empire and the Cardassian Union, equipped their computers with this feature.
200,000 years ago the Iconians equipped a facility launching Iconian probes on Iconia with a female computer voice. (TNG: "Contagion")
Starfleet starships utilized computer voices by 2256, a feature which continued to be used throughout the 23rd and 24th century. (DIS: "The Vulcan Hello"; TNG: "Encounter at Farpoint")
Kirk reacting to the reprogrammed computer voice
The computer voice of the USS Enterprise was reprogrammed in 2267 on Cygnet XIV, with the intent of giving it a less mechanized personality. The resulting modifications caused the computer to address James T. Kirk in an increasingly amorous manner, as well as giggle. This modification was short-lived. (TOS: "Tomorrow is Yesterday")
While most Starfleet computers utilized female voices, the M-5 multitronic unit in 2268 had a male voice. (TOS: "The Ultimate Computer")
In the alternate reality, the USS Vengeance had a male computer voice. (Star Trek Into Darkness)
In the mirror universe, the ISS Enterprise (NCC-1701) had a male computer voice. (TOS: "Mirror, Mirror")
After Bynar modifications to the USS Enterprise-D in 2364, the starship's computer for a short time used both the usual female and a male voice. (TNG: "11001001")
Starfleet environmental suits were also equipped with a computer voice. (Star Trek: First Contact; VOY: "Day of Honor")
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Background information Edit
The computer voice on most Federation starship and fixed installation computers was portrayed by Majel Barrett-Roddenberry since the early days of the original series (first appearing in TOS: "Mudd's Women"). The computer voice in TOS was very rhythmic and mechanical. In the later series, it became a far more normal-sounding female voice. Majel Barrett-Roddenberry continued to play Starfleet computers on TNG (with the exception of some early episodes), DS9, VOY, and many Star Trek films through 2009. Star Trek was her final performance both as the computer voice and in a Star Trek project before her death.
The computer voice on the ISS Enterprise (NCC-1701) in the mirror universe of TOS: "Mirror, Mirror" was provided by John Winston, the actor who portrayed transporter chief Kyle.
In the TNG episode "11001001", a USS Enterprise (NCC-1701-D) male computer voice was provided by an unknown actor.
Doug Hale voiced the upgraded USS Enterprise computer alerts in Star Trek: The Motion Picture.
Marcy Vosburgh provided a computer voice in Star Trek II: The Wrath of Khan.
In Star Trek III: The Search for Spock, the computer voice of the USS Excelsior turbolift was played by Director Leonard Nimoy, under the pseudonym "Frank Force". Harve Bennett provided the flight recorder voice in the same movie, during playback of scenes showing Spock's death from The Wrath of Khan. Judi Durand did a Spacedock computer voice that says, "Danger... space doors are closed" while the USS Enterprise is escaping from the station. Teresa E. Victor was the computer voice for the USS Enterprise self-destruct sequence in The Search for Spock.
The Cardassian computer system, as used on Star Trek: Deep Space Nine, was voiced by Judi Durand.
There is only a single word spoken by a computer voice in the entire run of Star Trek: Enterprise, which is when Majel Barrett's computer voice of the USS Defiant twice states "Working..." in the episode "In a Mirror, Darkly, Part II".
In Star Trek Into Darkness, the voice of the USS Vengeance was provided by Bill Hader.
In DIS: "The Vulcan Hello", the voice of the USS Shenzhou was provided by Tasia Valenza.
In DIS: "Context Is for Kings", the voice of the USS Discovery was provided by Julianne Grossman. In the Short Treks mini-episode ST: "Calypso", Discovery's computer, now a millennia in the future and having evolved into the artificial intelligence, Zora, was voiced by Annabelle Wallis.
In reality, when Google first developed voice technology, they named it "Majel" in honor of Majel Barrett. (After Trek: "Episode 2") Nowadays, Amazon Echo smart speakers can be adjusted to respond to the wake word "computer" (rather than "Alexa"), much as with the computer voice in Star Trek, and so-called "skills" based on the franchise can be enabled within such devices.
Apocrypha Edit
In many of Activision's video game releases, Judi Durand voiced the Federation computer voice.
In the Star Trek: Legacies novel Captain to Captain, Captain Una is momentarily distracted by hearing the Enterprise's computer voice after many years, which was modeled after her own.
