If you walk through the heart of Facebook's headquarters in Menlo Park, California, you'll find a rather imposing two-story mural painted by artist Brian Barnecio. It looks like a massive totem pole filled with abstract shapes that resemble lips and eyeballs and boxes of ping-pong balls, and in the middle of it all, there's a single word: "hack."

In the late 80s and on into the 90s and early 2000s, "hack" was a dirty word. It evoked danger and criminal activity. It was all about breaking into computer systems, telephone networks, and other vulnerable technology. People who knew their computer history disagreed, but the negative connotation took hold in the mainstream. But over the past decade, hacker has been rehabilitated. Today, it seems, everyone wants to be a hacker. Facebook has gone a long way towards renovating the word, building its massive successful company around the idea that hacking is a good thing, a way of transforming technologies into something better.

Hacking litters the Facebook campus. It was the subject of Mark Zuckerberg's pre-IPO manifesto, entitled "The Hacker Way." And every year, the company runs a campus-wide competition called "Hacktober," where employees break into each others systems with an eye towards making them stronger, not weaker.

Thanks to Zuckerberg, Facebook, and so many other ambitious software developers across Silicon Valley, hack is today a word with two meanings. We have white-hat hackers who build cool new apps and creatively blaze new paths, and we have black-hat hackers who brazenly compromise Sony's email systems.

What's the true meaning of the word? Was that it originally positive or negative? The question is more complicated than you might think. We can't give you a definitive answer, but we have turned up a new piece of the puzzle. Before it entered the world of technology, the word carried a special meaning in the world of 19th century cock fighting. And for what it's worth, it was a kind of attack, not a means of creation.

The MIT Origins

Hack dates back to at least the Middle English period (sometime between 1150 and 1500), and even in modern times, its evolution is rather byzantine. According to the Oxford English Dictionary, it arrived several hundred years ago, carrying another of its current meanings, namely to "cut with heavy blows in an irregular or random fashion."

But the sense that that gets thrown around Silicon Valley is, as you might expect, distinctly modern. You can trace its roots to the M.I.T. Tech Model Railroad Club, which in 1955 added this note to its minutes:

Mr. Eccles requests that anyone working or hacking on the electrical system turn the power off to avoid fuse blowing.

If you browse through back issues of The Tech, MIT's student newspaper, you can see it evolve, always maintaining the more playful meaning. A 1959 announcement for an upcoming Sigma Phi Epsilon circus party has one fraternity member promising to "'hack around' in a gorilla suit." And today at the university, "hacks" are what they call great pranks, preferably displaying awesome technical virtuosity.

For those in the black-hat camp, however, the clincher comes in November 1963. That's the first known reference to computer hacking, and in that case, it clearly describes a criminal trespass, with hackers connecting a PDP-1 computer to the MIT telephone system and launching what's known as a brute-force attack. The Tech's headline: "Telephone Hackers Active."

So the white-hat hackers get to say that their sense of the word is the oldest, while the black hats get to claim the first computer connection.

The Cock Fighting Connection

And now, we have a little bit of sand to throw into this age old and ultimately unresolvable dilemma. It comes courtesy Emily Brewster, an editor with Merriam-Webster. She dug through Merriam-Webster's archives and came up with this April 4th 1890 letter written to G. & C. Merriam & Co. by one A. W. Douglas, on the letterhead of the Simmons Hardware Company, of St. Louis Missouri.

Merriam-Webster

Douglas notes that the current dictionary omits a word that is used colloquially and originated in cock fighting. "When one cock whips another and the vanquished always afterwards runs when he sees the victor. It is the word 'hack,' and to be 'under hack' is to be afraid of some one," he writes.

Is it possible that southern cockfighting jargon somehow made the leap to the stately campus of MIT over 60 years later and then ultimately onto the walls of Facebook? Maybe. But Brewster doesn't think so. "I’m sorry to say we have nothing so definitive as a direct relationship between cockfighting and either goofy pranks or malicious computer related activity," she says. "It’s wholly possible that the meanings developed completely independent of one another."

Merriam-Webster, by the way, says that the two modern meanings of hack ("to write computer programs for enjoyment" and "to gain access illegally to a computer") are etymologically fused. "We have no evidence for these uses having different origins, so they’ll continue to have to share space in a single entry," she says.

Still, given the U.S. current hysteria about the threat of hackers, the image of a frightened chicken "under hack," carries at least a peck of metaphoric weight, even today.

Thanks for writing, Mr. Douglas.