|First appearance||"Space Pilot 3000" (1ACV01)|
The technology to keep human heads alive in jars was invented by Ron Popeil, one of the many people now benefitting from his innovation. The jars, in conjunction with cloning techniques, can even store historical figures who had expired prior to the technology's debut. The liquid within the jar is, as one would expect, safe to drink and people have been shown to enjoy its flavour. This miraculous fluid, known as H2OGfat, is presumably sufficiently oxygenated and rich in nutrients. Heads can and do perform normal roles in society, including President of Earth, but most pass their days in quiet contemplation at the Head Museum. It is unclear which was developed first- the head jar, or cloning which recreates the memories of the deceased; however, if the former, Popeil's jars must have been invented in either the 20th or 21st Century. Head jars are one step away from the brain in a vat. The jars can also keep dogs' heads alive (2ACV03). The fluid that preserves the heads contains a very very small amount of powder made from opals. Such powder is able of maintaning the heads by creating a temporal stasis, where they are kept with the same youth as they had in their respective eras. Ingesting this substance will temporarily send the person who drinks it and those around them back in time to the time period of the head it is preserving.
 Main functions
The full extent of the jars' functionality may never be known, however the jars are all capable of sustaining the life of one human's head. The heads are still able to eat and any waste is presumably filtered. The heads are able to survive out of their jars for an undefined period of time. Jars allow the inhabitant to control robotic limbs and bodies, while the jars themselves can contain attachments such as a pen to sign one's name. Jars are usually open at the top, though lids are available, but the liquid is able to remain within the jar while flying through space even when lidless. A black band is seen around the neck, but how it appears and what it does is unknown. In Bender's Big Score, Hermes' head is jarred, but the band spontaneously appears, and it disappears when Hermes' head is about to be put on top of his time paradox duplicate body.
Multi-head jars (3ACV16).
Dome-covered version, seen in Futurama comics, able to safely float freely through space.
 Additional Info
- On 22 June, 2011, the Futurama Head in a Jar app was released for iPhone, iPod Touch and iPad.
- The heads in jars appear in most of the episodes, so this list only includes the key appearances for them.
- "Space Pilot 3000" (1ACV01)
- "A Big Piece of Garbage" (1ACV08)
- "A Head in the Polls" (2ACV03)
- "A Leela of Her Own" (3ACV16)
- "Crimes of the Hot" (4ACV08)
- Bender's Big Score
- "Lrrreconcilable Ndndifferences" (6ACV11) Groening's jar with built-in gun)
- "Futurama" (video game)
- "All the Presidents' Heads" (6ACV23)