Aperture Science Handheld Portal Device


 * "There's a hole in the sky, through which things can fly!" - GLaDOS

The Aperture Science Handheld Portal Device, often referred to simply as the Portal Gun, is an experimental tool used to create two Portals through which objects can pass.

Development History
The Portal Device was the third stage of a three tier program set out by Cave Johnson on his deathbed in 1979, designed to guarantee his company's future. Up until this point Aperture Science had almost wholly concentrated on the research and development of shower curtains; Johnson thought that a device that could create "some kind of rip in the fabric of space...would help with the shower curtains I guess".

The least well thought out stage of the program, development on the Portal Device did not begin to bear fruit until 1981, after the first two stages of Johnson's program- the Heimlich Counter-Maneuver and the Take-A-Wish Foundation- had resulted in a P.R. disaster for Aperture. When summoned before a Senate investigative committee, however, an engineer stated that some progress had been made with tier three, which he referred to as a 'man-sized ad hoc quantum tunnel through physical space with possible applications as a shower curtain'. The committee was permanently recessed and Aperture were given an open-ended contract to continue work on both the Portal Device and the Heimlich Counter-Manuever.

Progress with the Portal Device was slow however, and in 1986 Aperture learned that Black Mesa were also beginning to investigate Portalling technology. In response to this Aperture constructed GLaDOS, a powerful supercomputer, which was completed and switched on some time after 1996.

It is not clear when the Portal Device in its final form was completed, or who in fact built it. A test subject named Chell was forced by GLaDOS to experiment with the device at the Aperture Science Enrichment Center; several prototypes, which only fired exit or entrance portals, were also seen in the initial levels of the Enrichment Centre. GLaDOS remarked to Chell that the Portal Device was more valuable than the sum value of the vital organs and incomes of every inhabitant of Chell's hometown. Chell used the Device to escape the facility.

Usage
The HPD has two firing modes, firing portal entrances and exits to make portals functional. The first type of portal is blue, the second orange. If one of each is present on the field, the two portal gateways are linked, allowing objects to pass through one end and exit at the other. The HPD is very useful when trying to overcome obstacles which would otherwise be impassable.

The HPD also has a weak zero point energy field manipulator which can carry fairly light objects, much like the Gravity Gun. It cannot, however, punt or launch objects; it can only drop or throw them a short distance. Nor can it pull them towards the user.

According to GLaDOS, though the portals have been proven 100% safe, the Handheld Portal Device has not: "Do not touch the operational end of the Device. Do not look into the operational end of the Device. Do not submerge the Device in liquid, even partially. Most important, under no circustances should you- (static)"

Trivia

 * The HPD cannot be used in Garry's Mod: although it's prop can be imported with the Portal content, it cannot be spawned as the working Device. Although a working version was made by fans for GMod 9, the latest GMod doesn't have the necessary code (although Valve gave the base Source Engine code to Garry Newman, it didn't contain the HPD code as it wasn't incorporated into any Source Engine games aside from Portal).
 * The ASHPD can be use in Half-life 2, its Episodes, and Half-life: source by simply copying all Half-Life game data into the Portal data folder. Then, use the cheat menu to type the Half-Life 2 map codes in the console. The Half-Life 2 maps will works seamlessly with the ASHPD and vice versa, partly because of development and system similarity.
 * Fans speculated that "ASHPD" was a nod to Adrian Shephard, the protagonist for Half-Life : Opposing Force. According to Valve, this is a simple coincidence.