My late father questioned why I described myself on my CV as a ‘mathematician and hacker’. I responded with this essay (January 2011)

The original hackers were a group from ~1975 onwards of computer hobbyists who disassembled machines, traded parts, and rebuilt them to improve them. The verb ‘to hack’ was already used by radio amateurs since the 50s to mean ‘to tinker’, as in Scrapheap’s challenge “we’ll fix that in tinkering time”. The hackers also wrote software for their computers, publishing their programs to share with and impress others. This was done in magazines made of paper! Two members of the Homebrew Computer Club around San Francisco’s Santa Clara Valley were Steve Jobs and Steve Wozniak, who founded Apple. Another member of the hacker community was Bill Gates, who founded Microsoft. That San Francisco valley is today called Silicon Valley.

These hackers modified their machines and wrote software to give them functionality that their manufacturers hadn’t intended, thought possible, or even considered. Observe that they owned their machines, so there is no question over the legality of their hobby. It is comparable to car enthusiasts serving their own car, who might ‘soup up’ its engine.

For the last thirty years, ‘hacking’ can also describe malicious modification of computers owned by other people. This happened at first by accident - in 1982 a game called Elk Cloner would as a practical joke by its creator display a poem on its 50th use. Shared on floppy discs, the game and the joke spread beyond its intended domain. Later those with perverse intent wrote viruses which would announce their conquest of a users computer before destroying data. Many of them were grumpy teenagers, which made a good news story. For the last fifteen years almost all hacking is done by organised criminals. It is a huge business. Viruses of 2010 do not announce their conquest but stay silent, they do not destroy a user’s data but silently collect it, so that the criminals may gain access their bank account. Rather than break a computer, the virus subverts it into sending spam (advertising for dodgy businesses and advance fee frauds). Such computers are called zombies.

These hackers who circumvent security - originally phreakers who whistled down telephone lines at the certain pitch to obtain free calls from the exchange, and since exploiting the internet are sometimes labelled ‘black hat’ or ‘white hat’ according to their morals. White hat hackers include security researchers.

Another two hackers of the first kind, the hobbyist kind, were Richard Stallman at MIT and Linus Torvalds at the University of Helsinki. Stallman (known by his initials, RMS) was concerned that as computer technology advanced it was becoming less accessible for tinkering by curious individuals. At MIT in 1980 he hacked the office printer so that it would message all users in the event of a paper jam. However hardware was becoming less important and much of computers functionality came from complicated software provided by the manufacturer, the operating system. The manufacturers did not publish their code, so hobbyists found it hard to fiddle with it, and the manufacturers frowned upon users sharing modified copies. Upset, from 1983 to 1989 Stallman wrote his own operating system, GNU, to replace the popular Unix operating system. GNU stands for “GNU’s not Unix”. Stallman shared all his code, and published it under a licence he wrote, the GNU Public License or GPL which explicitly encouraged users to modify his work and share it again. He called this ‘free software’ referring to liberty rather than price - free as in ‘free speech’ rather than ‘free beer’. Observing that software unlike physical goods can be shared without limit, he encouraged others to share their work, writing philosophy on why they should, and founding an organisation the Free Software Foundation.

In 1991 Linus Torvalds contributed a missing component to Stallman’s GNU project, the operating system kernel. Torvalds had yet to give his software a name when a friend shared it under the name Linux (the name of the proprietary kernel it replaced was Minix) and the name stuck. (Decades later, after criticism by those who thought the naming egotistical, Torvalds deliberately named his next software after himself. He called it ‘git’.) Torvalds shared Linux under Stallman’s GPL license, although he called it ‘open-source’ rather ‘free software’ and was more pragmatic than philosophical.

Mozilla Firefox, Google Chrome and VLC are modern examples of software released under Stallman’s free license encouraging collaboration and experimentation. Many people in the open-source community call themselves ‘hackers’ and the word ‘hack’ can mean to code. ‘To hack on Python’ would mean to contribute to the Python software project. They subscribe to the hacker ethic, that people should learn by tinkering, and understand and control their own machine. This hacker ethic extends beyond computers (as punk’s DIY ethic extended beyond music), hacker authors such as Cory Doctorow and Mark Pilgrim share their books freely online, yet still make a living selling paper copies. They argue that the much greater online audience begets greater sales, even if many people pay nothing. “The trouble authors have isn’t getting people to pay, it’s getting heard”.

Here are some examples of the word ‘hack’ to mean ‘to modify for a purpose not intended by the manufacturer’. 1. Make magazine’s ‘remote control lawnmower’. 2. The US Air Force’s supercomputer made from 2000 Sony Playstation 3’s for a budget of $2 million. 3. Jail-breaking the iPhone, the practise of ‘unlocking’ the software to allow users to install programs from outside Apple’s App Store, which refuses software Apple dislike. The practice of jail-breaking was confirmed legal in US court.

At MIT the word ‘hack’ as long been used to describe students practical jokes, from launching weather balloons during a football game with their rival Harvard, to this upside down living room (with working lamp) on a gate At Cambridge, perhaps the drinking culture stifles creativity.

The word ‘hack’ can also mean a solution to a problem. There are elegant hacks, and ugly hacks (these ones might involve lots of duct tape).

My Dad wrote back:

thank you, I see it has another meaning to that I understood. I think it is a word open to misinterpretation, so use with care!