A holodeck 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. It was discovered that matter and energy are interchangeable.

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.

Holodecks are equipped with safety protocols to prevent serious injury during their use, though these can be disengaged by the user when required. While active, a force field that is likely to cause a certain level of physical harm to a living humanoid collapses before making contact with them, allowing them to escape uninjured.

When protocols have been deactivated holographic obstacles would have the same effect on a person as a real one that existed outside a holographic environment; holographic bullets or a steep drop could be fatal in such a scenario.

How the security protocols are circumvented differs; in one instance, it required the voice authorization of two senior officers, while in others the authorization of the individual who started the program was enough.

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 and curiosity.

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.

Holodeck matter can impersonate real matter at the molecular level. Molecule-sized magnetic bubbles replace molecules in full resolution holographic object, which a computer can manipulate individually in three dimensions.

However, the complexity of electron shell activity and atomic motions that determine biochemical activity in living creatures cannot be projected holographically. 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 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 would not exist beyond the holodeck itself, as they only exist as energy.

A holodeck can modify the appearance of persons within it.

Holograms can be augmented with force beams to simulate solid, tangible objects or with replicator technology to create actual solid matter such as foodstuffs. All food 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".