Holodeck

A holodeck is a room equipped with a hologrid containing omnidirectional holographic diodes, enabling holographic projections.

Purpose & Design
The holodeck serves both entertainment and training purposes. It combines transporter technology with that of replicators, by generating holographic images in 3D space as well as projecting force fields to give the objects the illusion of substance. It can be controlled from an exterior control or the interior arch control. This arch can be summoned at any time to change the parameters of a running holoprogram.

Holodeck walls can generate holographic images that appear to extend for an unlimited distance, seemingly much larger than its own dimensions. In doing so, however, the holodeck is aware only of its users; it does not recognize its own created objects. For example, if a person were to throw a holographic rock at the holodeck's walls, the rock would not be allowed to pass beyond the wall. It does this by continuously adjusting the projections of the force fields and the use of a force field "treadmill". With this, an individual approaching a wall causes an instant shift away. The holodeck can change gravity in three dimensions, so occupants don't notice the change.

Holodeck matter can impersonate real matter even at the molecular level. Molecule-sized magnetic bubbles replace molecules in full- resolution holo-objects. The computer can manipulate them individually in three dimensions. The computer may use large magnetic bubbles to simulate surfaces and textures rather than create an object at the molecular level. However, Objects created within the holodeck could not exist beyond the holodeck itself, as they only exist as energy and matter.

A holodeck can modify the appearance of the persons in it. In Tom Paris' holoprogram "Captain Proton", everything and everyone can only be seen black and white. Seven of Nine used the holodeck to hide her cybernetic implants. However, it is unclear if this illusion works for Humans, because the only "persons" attending the program were Seven herself and the Doctor, who is holographic.

Holograms can also be projected into space. They can be augmented with force beams to simulate solid, tangible objects or with replicator technology to create actual solid matter such as foodstuffs. All foods eaten on the holodeck are replications. No other type of simulation would survive outside of the holodeck.

A holodeck also has the ability to create holodecks within holodecks, and holodeck programs are able to be saved to a cube that can be inserted into special devices with information to "last a lifetime".

Computers cannot duplicate the complexity of electron shell activity and atomic motions that determine biochemical activity in living creatures. This prevents replicators from duplicating life and resurrecting the dead. Advances in computer technology may allow this, permitting a person to live forever in any chosen environment while interacting with real people and objects visiting the holodeck.

The energy matrix of a holodeck is incompatible with other ship systems.

Failure of a holodeck's matter conversion subsystem can cause the loss of solid objects within the holodeck environment. Materialization errors occurred in the Enterprise-D holodecks in 2370 following the ship's exposure to plasmonic energy in the atmosphere of planet Boraal II.

Among the viewing modes on a holodeck is objective mode, in which the user doesn't interact with the characters, and subjective mode, in which the viewer can interact with the characters as well as alter his or her surroundings.

Early holodeck technology
Prior to the late 24th century, Federation starships were not equipped with holodecks. However, in 2151, the Earth Starfleet spacecraft NX-01 Enterprise encountered a vessel belonging to an alien race known as Xyrillians, who had advanced holographic technology in the form of a holographic chamber similar to the holodeck, which Federation Starfleet would develop two centuries later. A holo-chamber was later installed aboard a Klingon battle cruiser, given to the Klingons by the Xyrillians in exchange for their lives.

In the 23rd century, Constitution-class starships were equipped with a recreation room, which employed holographic technology. The USS Enterprise had a recreation room located in Area 39 of the ship.

Ferengi entrepreneur Plegg is credited with the development and introduction of the holosuite, a holographic chamber designed for use by one occupant at a time.

Federation holodecks
By 2364, the Federation Starfleet had begun installing holodecks aboard their vessels.

Federation holodecks are equipped with safety protocols to prevent serious injury during their use, although these can be disengaged by the user when required. If a forcefield would cause a certain level of physical harm to a living person that field collapses, allowing the person to escape uninjured.

How the security protocols are circumvented differs. In one instance, it required the voice authorization of two senior officers. In other instances, the authorization of the individual who started the program is enough. (Star Trek: Voyager)

Holodecks employ spatial orientation systems to simulate parts of a holocharacter, such as left- or right-handedness.

Holodeck characters have been known to include a program element designed to hide anachronisms to the program's time period, such as uniforms and communicators, and prevent them from raising the character's ire.

During the 2360s and 2370s, a starship could have one or more holodecks depending on the vessel's size. Nova-class starships, for example, did not have a holodeck, while Galaxy-class vessels had five. The two holodecks of Intrepid-class starships are the only places where the EMH can exist (without a mobile emitter) apart from the sickbay. In Prometheus-class starships, the EMH can move more freely because all decks are equipped with holoemitters.

Holoprograms
Starships with a holodeck normally had a vast list of holoprograms in its computer. Several notable programs aboard the USS Enterprise-D included:


 * A woodland setting, resembling Earth, which features a rock jumping challenge, some of which are seemingly impossible to complete.
 * A New Orleans jazz nightclub.
 * A recreation of the voyage on the Orient Express.
 * Sherlock Holmes Mysteries: Where the user takes on the role of Sherlock Holmes and/or Dr. Watson.
 * Prospero's island, decor for Shakespeare's "The Tempest".
 * Café des Artistes: "Enjoy a meal at a French cafe."
 * Champs Elysees: "Famous section of Paris."
 * Charnock's Comedy Cabaret: "Laugh in a 20th century comedy club."
 * The Big Goodbye: "The 1940's world of gumshoe detective Dixon Hill."
 * Emerald Wading Pool: "From planet Sumiko III, a safe experience."
 * Equestrian Adventure: "Horse riding in an open country..."
 * Calisthenics Program of Lieutenant Worf: a swamp-like setting where various alien enemies test one's fighting skill.
 * The Bridge of the U.S.S. Enterprise: the user could select any of the five (at the time) bridges of the various Federation starships named Enterprise to view. Captain Montgomery Scott only wanted to see the original Enterprise bridge, "no bloody A, B, C, or D."
 * The Final Mission of Enterprise: This program allows a user to view or take part in the final mission of the NX-01 Enterprise, commanded by Captain Jonathan Archer, as well as showcasing the signing of the Federation charter.
 * Tasha Yar's Living Will: Designed by Lieutenant Tasha Yar to be played in the event she was killed where she bids farewell to her comrades. The Enterprise bridge crew unfortunately had to watch the program when Yar was killed by Armus on Vagra II.
 * Celtris III Underground: Where the users can prepare for missions on the Cardassian planet of Celtris III.
 * Lieutenant Barclay's Various Programs: Including a mock-up of Ten Forward where the user can attack Commander Riker and Lt. Commander Geordi La Forge to "blow off some steam" as well as win the heart of Deanna Troi, a mock-up of Counselor Troi's office where the user can receive counseling from a hologram rather than the real Troi, a woodland setting where the user can duel with recreations of Captain Picard, Mr. Data, and Geordi in a sword-fight; complete with a recreation of Deanna Troi as "The Goddess of Empathy", a mock-up of the Enterprise-D bridge where the user can bid farewell to the bridge crew, the Einstein program where the user can debate mathematics and science with Albert Einstein, a synaptic interface where the user can control the main computer of the Enterprise with the power of their own thoughts (however, removal of the user by conventional means would result in death), and various other programs.
 * HMS Enterprise: An 18th Century earth oceanic vessel.

Notable programs aboard the USS Enterprise-E included:
 * The Big Goodbye: "The 1940's world of gumshoe detective Dixon Hill."

Notable programs aboard the USS Voyager included:
 * Chez Sandrine
 * Captain Janeway's Gothic Holonovel
 * Insurrection Alpha
 * Leonardo Da Vinci's Workshop
 * The Adventures of Flotter
 * Velocity
 * The Adventures of Captain Proton
 * Fair Haven

Notable programs aboard the USS Enterprise's recreation room included:
 * A beach setting allowing for swimming.
 * A woodland environment allowing for a nature walk.
 * An arctic wasteland.
 * An 18th century style hedgemaze.