Big iron, as the hacker's dictionary the Jargon File defines it, "refers to large, expensive, ultra-fast computers. It is used generally for number crunching supercomputers such as Crays, but can include more conventional big commercial IBM mainframes".
The term is often used in reference to IBM mainframes, often when discussing their comeback/survival after the assault of lower cost Unix systems. More recently the term is also applied to powerful computer servers and computer ranches, whose steel racks naturally invoke the same association.
The expression may be compared with the slang expression for heavy handguns, derived from the slang "iron" for a handgun ("shooting iron"), as exemplified by the classic country music ballad Big Iron by Marty Robbins about "the ranger with the big iron on his hip".
Famous quotes containing the words big and/or iron:
“Everything our children hear, see, and feel is recorded onto a cassette. Guess who is the big star in their movie? You are. What you say and, more important, what you do, is recorded there for them to replay over and over again. We all have videocassettes. Adults just have larger libraries of tapes available.”
—Stephanie Martson (20th century)
““Ego non baptizo te in nomine patris, sed in nomine diaboli!” deliriously howled Ahab, as the malignant iron scorchingly devoured the baptismal blood.”
—Herman Melville (1819–1891)