In 1979 Raymond Nickerson and Marilyn Adams asked American adults to draw a one-cent coin from memory. Of its eight main features, the typical drawing had three right and in the right place, and the only person to get all eight was a coin collector. Shown fifteen drawings of a penny, fewer than half of another group picked the real one.

In 2015 Adam Blake, Meenely Nazarian and Alan Castel asked 85 students at UCLA to draw the Apple logo. One drew it perfectly. Given the real logo among altered versions, 47 percent picked it, and the students who used only Apple products did no better than the rest. Drawing it humbled them: in a follow-up, confidence fell from 8.6 out of 10 before drawing to 5.5 after.

Deepasri Prasad and Wilma Bainbridge tested 40 famous logos and characters in 2022 and found seven that people misremember in the same way. The Monopoly man has no monocle, Pikachu's tail has no black tip, there is no cornucopia behind the Fruit of the Loom fruit, and one of C-3PO's lower legs is silver. Memory fills a gap with what seems likely, and fills it alike in millions of heads.

Bae, Olkkonen, Allred and Flombaum (2015) found that a remembered color mixes its category, such as blue or green, with an estimate of the exact shade, and that memory pulls it toward the center of its category, by up to 10 degrees of hue. A brand color that sits between two names, a teal, a coral, a violet, has the most room to drift.

In 2013 Atsushi Kimura and colleagues asked students in Japan to adjust twelve food and drink logos until each looked gray. For the logos they knew well, the setting that looked gray was pushed away from the brand's own color, so a truly gray logo still carried a trace of it. Logos they barely knew showed no effect, and the more stores a brand had, the stronger the pull.

Since C. J. Bartleson's study of 1960, colors recalled for familiar things have come back more saturated than the real ones: grass greener, brick redder. A brand color you are sure of is likely to be a little paler than the one you picture.

Tiffany traces its blue to the cover of its Blue Book catalog, first published in 1845, yet its own press office says there is no definitive answer as to why that shade was chosen. It has been a registered color trademark since 1998, and since 2001 a custom Pantone, 1837 Blue, named for the year the company was founded and not sold to anyone else.

UPS says it painted its cars brown in 1919, the year the name United Parcel Service first appeared, for a color that stood for class, sophistication and professionalism. The brown, close to Pantone 462C, is now a registered trademark on its vehicles and uniforms, and in 2002 the company built a whole campaign on the question What can Brown do for you?

By Hermès's own account, its box maker ran out of the cream boxes with gold edging as the Second World War drew to a close. All that was left was orange paper, the kind nobody wanted. The house used it, and the orange box became the brand.

Mark Zuckerberg found out from an online test that he is red-green color blind. Blue is Facebook's color, he told The New Yorker in 2010, because blue is "the richest color for me": he can "see all of blue."

In 2009 the designer Douglas Bowman left Google, writing that a team unable to choose between two blues for its links was testing 41 shades in between. In 2014 the head of Google UK told The Guardian that a slightly purpler blue had beaten a slightly greener one, and earned an extra 200 million dollars a year in advertising.

A color has to acquire what courts call secondary meaning. Owens-Corning had made its insulation pink since 1956 and spent more than 42 million dollars advertising it, Pink Panther commercials included. When a survey asked homeowners who made pink insulation, 41 percent named Owens-Corning, and 50 percent after a run of the Pink Panther ads. In 1985 the Federal Circuit let it register the color.

A color that does a job cannot be locked up. In 1982 a federal court in Iowa refused to let John Deere stop a rival selling front-end loaders in Deere green, because farmers want their loaders to match their tractors. Qualitex's green-gold passed the same test: other colors hid stains on a press pad just as well.

In 2014 a court in Texas stopped AT&T's Aio Wireless from covering its marketing in large blocks of plum, Pantone 676C, after T-Mobile showed that 56 percent of people surveyed linked its magenta to T-Mobile. A rival does not have to copy a color exactly to be told to stop.

Cadbury has wrapped Dairy Milk in purple since 1914. In 2013 the Court of Appeal of England and Wales still struck down its registration of Pantone 2685C, because the application covered purple on the whole wrapper or as its predominant color: several possible signs rather than one.

In 2012 the Second Circuit limited Christian Louboutin's red-sole trademark to soles that contrast with the rest of the shoe. A red sole on an all-red shoe does not infringe.

Screens mix red, green and blue light, so a screen color is three numbers from 0 to 255. A hex code writes them as a hash and three pairs of hexadecimal digits, #rrggbb: 256 levels a channel, 16,777,216 colors, and the form the true colors in this game are stored in.

Cyan, magenta, yellow and black, the key plate: the four inks of ordinary color printing, and the usual way to specify a color for the printed page.

Numbered inks from the Pantone Matching System, which Lawrence Herbert introduced in 1963 so a designer could name a color and any printer could match it. Pantone numbers are how a brand writes its color into a contract or a court filing, and since 2000 the company has also named a Color of the Year, starting with Cerulean.