“That blue represents millions of dollars and countless jobs,” she says. “And it’s sort of comical how you think that you’ve made a choice that exempts you from the fashion industry when, in fact, you’re wearing the sweater that was selected for you by the people in this room.” In reality, it was selected by Pantone. Six years before the release of “The Devil Wears Prada,” Pantone’s forecasters named cerulean the company’s first-ever Color of the Year.

In the nearly two decades since then, as digital design and social media have expanded the ranks of color obsessives, Pantone has become not just a company but a sensation, its brand bestriding the globe like a behemoth. Its color forecasts, too, have retained their reputation as some of the most influential in the world, even as the field of competitors has grown crowded — not just with other companies but, thanks to the internet, with people on social-networking sites like Tumblr and Pinterest who have a knack for spotting color trends and enough followers to matter. For the class of fashion and industrial designers who make up Pantone’s customer base, picking the right color — and exactly the right shade of that color — can feel like one of the most important decisions they’ll make all year. Companies will pay almost anything to get it right, and the rarefied, vaguely mystical art of doing just that happens to be Pantone’s business.

For most of history, dyestuffs were derived only from natural materials like plants, minerals and invertebrates, offering people a narrow range of colors from which to choose. Only the rich could afford to clad themselves in more-exotic hues. This changed in the mid-19th century with the rise of the synthetic chemical industry. In London, in the spring of 1856, a college student named William Henry Perkin was experimenting with aniline, an organic compound he extracted from coal tar, in an attempt to synthesize quinine, an antimalarial drug then in great demand among inhabitants of the British Empire’s equatorial possessions. As Regina Lee Blaszczyk recounts in her 2012 book, “The Color Revolution,” the experiment failed but by accident produced a dark, viscous substance. It happened to stain a rag, and presto! Mauve was born. Two years later, Princess Victoria, the queen’s oldest child, was married in a mauve dress, igniting the world’s first fashion craze for a synthetic color.

More discoveries soon followed: magenta, Hofmann’s violet, Lyons blue, malachite green, Bismarck brown and aniline black. By the 1880s, dye houses in Germany, which was by then the center of the chemical industry, and French textile mills were issuing seasonal color cards and ribbon samples of various synthetic shades. When the outbreak of World War I cut off the supply of German dyestuffs, threatening the color industry with collapse, a consortium of American mills and manufacturers formed the Textile Color Card Association, which developed the first industrywide color library and trend forecast, based solely on dyes that could be manufactured domestically. After the armistice, the group continued to be a hub for the best intelligence on color trends emanating from Europe’s fashion capitals and, in 1955, renamed itself the Color Association of the United States. Similar organizations soon took form in other countries around the world.

The modern color industry had arrived, if only in a confined sort of way. Born out of the fashion business, it remained rooted there for decades even as it exerted powerful influence on distant parts of the consumer economy, such as the automotive and home-furnishings sectors. But at the turn of the millennium, the color industry’s center of gravity shifted seemingly overnight with a big bang in the field of industrial design: the release, in 1998, of Apple’s iMac G3 desktop computer.

Available in 11 translucent shades, from Bondi Blue to Tangerine, the iMac ushered in a new era in which consumers began to value everyday purchases not strictly, or even primarily, for their utility but as a form of self-expression. “That colorful plastic was everywhere in industrial design for the next several years,” Virginia Postrel, the author of several books on aesthetics, told me. “Not just consumer electronics but all sorts of ordinary objects like irons and trash cans. It was an easy and cheap way to make things look fun and fresh.” Eventually, the enthusiasm faded; Apple itself shifted its palette to neutral whites, blacks and silvers. But the larger idea that the iMac inaugurated — namely that color choices are serious business and can determine the success or failure of any product in any industry — continues to ripple through the marketplace.

Steve Jobs’s revolution in commercial aesthetics would have been impossible without another one that occurred 35 years earlier. A nagging problem had troubled the color industry from its inception: how to communicate accurately the subtleties of perception. In his 1963 book, “Interaction of Color,” the Bauhaus artist and Yale professor Josef Albers wrote: “If one says ‘Red’ (the name of a color) and there are 50 people listening, it can be expected that there will be 50 reds in their minds. And one can be sure that all these reds will be very different.” There are innumerable colors, he continued, but only about 30 names for them. And even if you could describe all of those colors, wouldn’t your sense of them still differ from someone else’s? As the British journalist Kassia St. Clair writes in “The Secret Lives of Color,” “You could no more meaningfully secure a precise universal definition for all the known shades than you could plot the coordinates of a dream.”