After having a radioactive spider bite him, inject its irradiated venom into his bloodstream, and give him its powers in the instant of its own death, Peter Benjamin Parker realized that he had, in effect, become a human spider--a Spider-Man. He decided that a Spider-Man was nothing without a web, and so invented the wrist-worn devices he called his "web-shooters." Initially meant to be tools of the professional stuntman's trade he had initially hoped to pursue, they have instead become his chief weapons as a crusading adventurer since, after he came to believe that he could have prevented the murder of his uncle, Benjamin Parker, his reluctant abandonment of those professional ambitions in favor of the unpaid work of fighting crime, which he pursues on the principle that "with great power, there must also always be great responsibility."
The devices have remained the same throughout most of Spider-Man's career. When he was transformed and given organic web-shooters, Peter modified his mechanical web-shooters into bracelets for Mary Jane Watson to wear. However, that seems to have been retconned after the events of One More Day and Brand New Day. Ben Reilly donned modifications of them that he wore outside the wrists of the costume's gauntlets and allowed him to fire other web-like projectiles. Spider-Girl wears her own versions of the Web-Shooters.
One of the few modifications Spider-Man has made to the web-shooters is a red LED light, that will blink and let him know when he is about to run out of web fluid. Another upgrade is a small launcher on the back of the hand, which allows him to fire off his spider-tracers. In recent years, he has modified the shooters to fire on voice-command. 
Creation of the Shooters, and Spider-Man's Webs
Spider-Man's web-shooters are twin devices, worn on his wrists beneath the gauntlets of his costume, that can shoot thin strands of a special "web fluid" (the chemical composition of which is not known) at high pressure. (Note: The fluid itself is officially described as being pressurized at 300 psi, but the actual number has been known to change.) The spinneret mechanisms in each web-shooter are machined from stainless steel, except for the turbine component, which is machined out of a block of Teflon, and the two turbine bearings which are made of amber and artificial sapphire. The wristlets and web-fluid cartridges, the latter of which Spider-Man wears on his belt beneath his costume's tunic, are mainly nickel-plated annealed brass. The wristlets have sharp steel nipples, which pierce the bronze caps when the cartridges are tightly wedged into their positions.
The hand-wound solenoid-needle valve on each web-shooter is actuated by a palm switch; this in turn, is protected by a band of spring steel which requires a 65-pound pressure to trigger it. The switch is situated high on the palm to avoid most unwanted firings. An additional safety measure, to prevent misfires while Spider-Man is making a fist or carrying things, is that the trigger has to receive a double-tap from Spider-Man's middle and third fingers. The small battery compartment is protected by a rubber seal.
The effect of the very small turbine pump vanes is to compress (shear) the web fluid and then force it, under pressure, through the spinneret holes, which cold-draws it (stretches it: the process wherein nylon gains a four-fold increase in tensile strength), then extrudes it through the air where it solidifies. As the web fluid exits the spinneret holes, it is attracted to itself electrostatically, and thus can form complex shapes. The spinneret holes have three sets of adjustable, staggered openings around the turbine which permit a single, incredibly strong line; a more complex, spreading spray; and a thick, tremendously adhesive liquid.
The web line's tensile strength has been estimated to be 120 pounds per square millimeter of cross section. The 300 p.s.i. pressure in each cartridge is sufficient to force a stream of the complex web pattern an estimated 60 feet. (It goes significantly farther if Spider-Man shoots it in a ballistic parabolic arc.)
Peter Parker devoted many hours of practice to weaving his webs in many different ways: as a shield, a parachute, a safety net, a barrier, skis, a raft, a club, a ball, or sticky glue. By weaving his webs into discs beneath his feet, he can walk across water  or fire. Given enough time, Spider-Man can even create sculptures out of his webbing, which will turn into a sticky mess on anyone who takes a swing at them.
Web fluid is a shear-thinning liquid (virtually solid until a shearing force is applied to it, rendering it fluid) whose exact formula is unknown, but is related to nylon. On contact with air, the long-chain polymer knits and forms an extremely tough, flexible fiber with extraordinary adhesive properties. The web fluid's adhesive quality diminishes rapidly with exposure to air. (Where it does not make contact with air, such as at the attachment disk of the web-shooter, it remains very adhesive.) After approximately 1 hour, certain imbibed esters cause the solid form of the web fluid to dissolve into a powder.
At one time, Peter sought to sell the formula for webbing to make money, but the company to which he tried to sell it did not want it, not seeing the use for such a short-lasting glue. When Otto Octavius took over Peter's body, he modified the webbing to last far longer than Peter's and made it much stronger. Peter would later learn of the improved webbing, after reclaiming his body, he was forced to make web underwear due to circumstances and, when it refused to dissolve after the usual hour, was forced to wear pants instead of his costume bottom until Anna Maria showed him where the new solvent was.
Because the fluid almost instantly sublimates at its anaerobic liquid/solid phase transition point, there is no clogging of the web-shooter's parts.
Specialized Web Fluids
- Ice Webbing was created specifically to combat the Human Torch. This webbing was able to hold him temporarily, until he concentrated on burning at a higher temperature. Spider-Man subsequently discovered that his standard webbing was able to accomplish the same feat, though in a less flashy manner. Presumably, this is why he rarely used this variant.
- Acid Webbing was concocted after a string of murders led to William Baker, the Sandman. Peter concocted special webbing laced with hydrochloric acid, which could dissolve the individual granules of the Sandman's body. It proved successful in incapacitating him but not killing him, as Peter stated he was not sure if anything could really kill him. Because the webbing looked the same as his original formula, Peter placed it into a green cartridge instead of the usual grey.  He has also used this type of webbing as early as his initial encounters with the Rhino.
- Magnetic Webbing is the newest variation of Spider-Man's original web-formula, with magnetized particles that will interfere with any remote-control frequencies.
- Flame Webbing is useful against symbiotes. When Spider-Man fires it, his web-shooters eject a highly combustive chemical solvent from the ports, that will burst into flames upon contact with the intended target when entrapped in enough fluid.
- Taser Webbing generates a bio-electric current within its semi-liquid substance; Spider-Man can use it to temporarily stun his opponents.
- Expanding Web-Foam is webbing that becomes foam once it comes out of the web-cartridge.
Alternate Reality Versions
|In Earth-120703, Peter Parker used parts from two wrist watches and Oscorp spider silk technology, to succesfully create a high pressure launching system to fire the adhesive "webbing."||The Amazing Spider-Man (2012 film)||Two years later Peter enhanced his web-shooters.||The Amazing Spider-Man 2 (film)|
- On Earth-26496, it has been said that web fluid adheres to fibrous substances, but also (jokingly) that it can be removed from human hair using ice or peanut butter.
- On Earth-13017, web-fluid becomes rancid if not used in a while.
- The newest formula, created by Otto, keeps the web active until he activates a dissolving agent.
- 3,162 Appearances of Web-Shooters
- Media Web-Shooters was Mentioned in
- 106 Images featuring Web-Shooters
- Item Gallery: Web-Shooters
- Fan-Art Gallery: Web-Shooters
Links and References