words Adam FisherIn the simplest terms, a pixel is a dot, but you rarely find just one. They travel in packs. Your computer screen, most likely, arranges them in a 1280 x 1024 phalanx - a megapixel, roughly. The word itself is a portmanteau, a blending of the words "picture" and "element." And according to the Oxford English Dictionary, it was first introduced to the reading public in the pages of Science magazine in 1969, in an article that explained just exactly how NASA spacecraft beamed the first pictures of Mars back to Earth. One of the authors of that article, the atmospheric scientist Andrew T Young, is "mildly horrified" to be associated with the word. "I thought it was a vile neologism, and tried to avoid it myself," he has said, blaming the word on his colleagues at NASA's Jet Propulsion Laboratory.
The pixel that we're most familiar with, the ones that light up our computer screens, did not come directly from NASA, exactly. They arrived in our homes courtesy of Atari founder Nolan Bushnell, who, 25 years ago, released Pong - the game that brought the pixel from the computer lab into people's lives. It was the first of many. "In the early days, before colour, we split up the screen into 256 by 256, and we spent a lot of time filling in squares in graph paper to make something that looked like a rocket, or a car, or a man running," says Bushnell. "One pixel could completely change the image, it was an interesting art."
These days, the pixel has gained heft, something analogous to mass. Our advanced computer graphics systems describe their 3D worlds as an array of "voxels" - short for "volumetric pixel," the atomic unit of cyberspace. Even more advanced systems map light with "luxels" - think photons. Surfaces are rendered with "textels". Yet even if you exclude all the newfangled "els," there are likely more pixels in the world than any other flavour of digital information. Twenty five percent of all internet traffic is pixelated, and will exceed all other traffic combined by 2012.
And that's not counting the pixels that are even still raining down from the heavens. The highest resolution cameras in the world are spy satellites, which are taking digital pictures of you and me right now, from space. The best guess is that those cameras are in the gigapixel range (no one but the government knows, and they're not telling), which would make one of us humans, viewed from orbit, about a pixel wide.
Now might be the time to ask if a single pixel can ever matter anymore, if one pixel can still completely change the image, if one pixel can still make the ordinary into art. The answer depends, strangely enough, on the type of pixel. The pixel itself is ambiguous, for a pixel can mean one of two things. A pixel can be a unit of measure: "megapixel" or "a pixel wide." But the pixel can also be a unit of creation - think of Bushnell, filling in squares of graph paper. It is the difference between looking down on the world, as does the gigapixel spy-cams that orbit in space, and looking up at those same heavens, and to the ultimate creator.
It may be a stretch, but I put Bushnell's Pong on a continuum that leads eventually to German artist Gerhard Richter who, in 2007, installed an artwork in the south transept of the cathedral in Cologne. It's a stained-glass window made of small, square, coloured panes of glass arranged in a grid - pixels.