A wire is simply put a rope made of metal (usually steel) strings instead of hemp or synthetic fibre. There are numerous ways of winding strings together to form the wire, depending on the thickness and durability the end product is supposed to have. Before wires, chains were used to much the same effect.
The telegraph was for a while called "the wire". That usage is still evident in the verb "to wire", meaning to send information by means of a telegraph.
Wire is also a rock band. Wire emerged out of the English rock scene in the 1970s to make an indelible mark on punk rock. They are usually associated with the beginnings of an all-inclusive subgenre called "art-punk." In 1977, they released their first album, Pink Flag, which included 21 songs, many of which were under a minute-and-a-half long with no standard verse-chorus-verse-chorus structure. The combination of obscure lyrics ("Brazil", "Strange", and "Surgeon's Girl"), critiques of commercialized culture ("Ex-Lion Tamer" and "Mr. Suit"), and melodic power pop ("Mannequin" and "Fragile") all gave Pink Flag a depth that other punk rock bands neither achieved nor much desired. But Wire maintained an intense, overdriven sound that also heralded the hardcore of the 1980s, prompting hardcore icons Minor Threat to cover Wire's "12XU" on the Flex Your Head compilation on Dischord Records.
Their later albums, Chairs Missing and 154, found the band experimenting with more moody sounds and synthesizers. Wire thus helped to galvanize more than punk rock, but also set the stage for the new wave and electronica that permeated the next two decades of popular music. Wire disbanded soon after, but regrouped in the late 1980s to perform a dark brand of techno-pop almost exclusively. Nonetheless, guitar-driven bands have found the most direct connection to Wire, from the Minutemen to REM, who did a faithful rendition of "Strange" on their album Document.