(Kevin Lamarque/Reuters)

Writing on the Internet, no one can hear you scream. Unless, of course, you use all-capital letters.

At 6:35 p.m. on Thursday, President Trump tweeted, “SEE YOU IN COURT, THE SECURITY OF OUR NATION IS AT STAKE!” This was the president’s reaction to a ruling by the U.S. Court of Appeals for the 9th Circuit, which rejected the government’s attempt to unfreeze the ban on travelers from seven majority-Muslim countries. That was just after the victorious attorney general of Washington tweeted “DENIED. UNANIMOUS. PER CURIUM,” apparently too overjoyed to spell “curiam” correctly.

It is “highly unusual” for a president to rely on all-capital letters in public messages, as Stephen Huxley, chair of communication and digital media design at Australia’s Swinburne University of Technology, told The Washington Post on Friday.

“If your message is good, your message is clear, you don’t need to add emphasis. It’s irrelevant,” Huxley said. Resorting to all-capital letters signals that there has been a breakdown between sender and receiver. Huxley likened it to a person who, struggling to communicate with someone who speaks a foreign language, not only repeats a message but shouts it. Such an all-capitalized message demonstrates typographic “poor form,” he said. “It’s rude and received as rude.”

For those who fear that the president lacks the temperament befitting the office — and, as The Washington Post reported in February, a majority of voters in Fox News’s Election Day exit poll felt this way, including 1 in 4 Trump voters — a tweet in all capital letters is not likely to relieve such concerns. Slamming down the caps lock button, as a convention to express emphasis or a loud voice, has Internet roots dating back to the early 1980s.

For Trump, all-caps is a frequent Twitter motif. His all-uppercase words and phrases have persisted after the inauguration. Since Feb. 1, Trump used all-caps to tell the country of Iran it was “PUT ON NOTICE” for launching a ballistic missile, repeatedly called various media outlets or reporters “FAKE NEWS” and, several times, blasted his campaign slogan “MAKE AMERICA GREAT AGAIN!”

But all-caps did not always signify someone was sounding off a yawp about “EASY D!” In fact, for thousands of years of written language, the distinction between uppercase and lowercase letters did not exist.

If you wanted to write about a pleasant day in Mesopotamia, or turtles or Socrates or anything else, it was capital letters all the way down. The association with antiquity — feats of great Romans, for instance, were chiseled in all-caps — is why capital letters accumulated a sense of “grandeur,” “pomposity” or “aesthetic seriousness” over the course of millennia, as Paul Luna, an expert in typography and graphic communication at the University of Reading in Britain, explained to the New Republic in 2014.

By the 3rd century, the Greeks developed a way to write letters in minuscule, or shortened forms of uppercase letters. The purpose of minuscule was to speed up writing books by hand while keeping the text legible. But there was no meaningful division between a word written in majuscule, equivalent to uppercase, and minuscule. 

During King Charlemagne’s Carolingian Renaissance, a group of monks led by English scholar Alcuin of York produced the Carolingian minuscule script, meant to be read across Europe. It proved to be a success, forming the basis for modern Roman type. By the early 15th century, minuscule morphed into lowercase, and the Latin alphabet solidified as the two-part system we use today. “For uppercase types they used types based on stable, capital letters of ancient Rome,” wrote Croatian media designer Mario Tomiša and his colleagues in 2013 in the journal Technical News. “On the other hand, lowercase types derived from Carolingian soft and warm script.”

Although there was a clear divide, capitalization was mostly used for aesthetic sentence structure rather than emphasis. “Whether it was a polite message or a rude message, there was still never the need to put things in all capitals,” Huxley said. The information in the message is what was important, in other words, not which case you used. “As a typographic device, it was a decorative thing,” he said, “not a shouting mechanism.”

At some point by the 1940s, writers like Philippa Schuyler became “fond of using caps to yell,” as the pianist wrote in her biography, according to the New Republic. But the emphatic capital’s true reign of terror occurred on the Internet. Ben Zimmer, a language columnist for the Wall Street Journal, pointed the New Republic to a 1984 Usenet newsgroup (a precursor of sorts to today’s forums and message boards), in which one user declared, “if it’s in caps i’m trying to YELL!” Other forms, such as spacing out the letters of a word (like t h i s) or asterisks (*like this*), were proposed around the same time, but did not spread as widely.

To Huxley, email subject lines proved to be the fertile ground where emphatic all-caps flourished. Emails began to sport headers like “YOU MUST READ THIS” or “URGENT” as a way to cut through increasingly noisy inboxes. (It’s still poor form, Huxley noted.)

Since then, the Internet has had two polarizing effects on capitalization. One was that younger users, brought up with a more casual attitude toward capitalization, began eschewing capitals completely. “I think in the future, capitalization will disappear,” said Richard Sterling, a teacher at University of California at Berkeley and director of the National Writing Project, to the New York Times in 2008. He envisioned that certain Internet conventions, such as an utter lack of capitalization in casual emails, could become acceptable forms of writing. “I think this is not a worrying issue at all,” he told the Times, noting how language evolves over time.

Conversely, municipalities and government agencies became sensitive to issuing all-uppercase messages. In April, the National Oceanic and Atmospheric Administration announced it would stop sending out uppercase weather reports, which had been a holdover from the caps-only teletype. “In fact,” NOAA noted in a news release, “in web speak, use of capital letters became synonymous with angry shouting.”

New York City began to move away from all-capital Highway Gothic in its street signs in 2013, replacing the font with a mixed-case text named Clearview. The Federal Highway Administration ordered signs to be changed back to Highway Gothic in January 2016, a controversial move in design circles. (“Helen Keller can tell you from the grave that Clearview looks better,” one critic said at the time.)

Huxley, who was speaking to The Washington Post by phone while his wife drove through downtown Melbourne, began pointing out the typography of road signs. All-caps was reserved for single words, like STOP, or warnings, like MEN AT WORK. 

“All road signs that are instructional are upper- and lowercase,” Huxley said. In other words, information was written in sentence case, whereas orders and commands were associated with uppercase only. “I don’t know if Trump knows this, but I don’t think he cares,” the typographer said. “Trump is a man of limited gestures.”

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