Decoding language

10 punctuation secrets your teachers never told you

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Punctuation shapes how we read, write, and think—yet it often goes unnoticed until its absence makes a sentence hard to understand. Most punctuation marks weren’t always part of the language; many have surprising backstories, and some are even relatively recent additions to English grammar. Here are the stories behind 10 marks that give structure—and meaning—to our sentences.

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The period began as a simple dot used by Aristophanes of Byzantium to mark the end of a sentence. Its purpose was to improve clarity in long manuscripts, at a time when spaces between words did not exist.

Over the centuries, it evolved into the familiar punctuation mark we know today, becoming a universal symbol of grammatical correctness.

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The comma was added in the 3rd century BCE to indicate a brief pause while reading aloud. Its name comes from the Greek komma, meaning "a piece cut off."

It was later popularized in the Renaissance to structure complex sentences, helping writers convey rhythm and meaning more clearly.

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Italian printer Aldus Manutius introduced the semicolon in 1494 to separate closely related independent clauses.

It became a favorite among scholars, as it allowed nuanced connections between ideas without fully breaking a sentence.

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The colon was also popularized by Manutius, used to introduce lists or explanations.

It historically guided readers in written speeches or complex texts, marking a shift in thought or attention to important details.

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The question mark likely comes from the Latin word quaestio, which was often abbreviated as ‘qo’ at the end of sentences.

Scribes eventually stylized the abbreviation into the curved mark we use today, which has become a universal signal for a question or inquiry.

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Introduced in the 16th century, the apostrophe marks omitted letters and abbreviations, as in don’t from do not.

It also indicates possession in English; however, its use in that sense didn’t become standardized until the 18th century.

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The hyphen emerged in the Middle Ages to join words or split lines. Printers sometimes used it to avoid awkward spacing.

Today, it joins compounds like well-being or divides words at line breaks, helping preserve clarity in written language.

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Parentheses were introduced in the 15th century to provide supplemental information without breaking the main text.

They guide readers through secondary thoughts, examples, or clarifications more efficiently.

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Did you know that the ampersand is a ligature of the letters "e" and "t"? Together, they form et, the Latin word for "and."

Used since Roman times, it became a typographical shorthand as well as a symbol of elegance in logos and design.

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Created in 1962 by Martin K. Speckter, the interrobang combines a question mark and an exclamation mark into a single symbol.

It expresses surprise and inquiry simultaneously, though it never became a standard punctuation mark. However, using both signs together is common in comic books and informal writing to convey the same effect.

Tango, Bravo

Codewords decoded: How many did you know?

In situations where clear communication is paramount, especially when lives are at stake, professionals often rely on standardized codewords and phonetic alphabets designed to prevent confusion. Either from movies or from personal experience, it's probable that you've heard at least some of these before, and many have found their way into everyday conversation. Let's find out how many of these code expressions you can recognize.

Mayday is the international distress call used when the sender is in immediate, life-threatening danger. Pilots and mariners use it to signal that they require urgent assistance due to situations such as engine failure, fire, flooding, or medical emergencies.

The word was introduced in 1923 by British radio officer Frederick Stanley Mockford, who based it on the French phrase m'aider, meaning "help me," in an attempt to make it internationally recognizable. Hearing this transmission immediately alerts emergency responders that every second counts.

Not every emergency is severe enough to warrant a mayday call. When a crew faces a problem that is urgent but not immediately life-threatening, the appropriate codeword is Pan-Pan.

Like mayday, it comes from French: it derives from panne, meaning a breakdown or mechanical failure. A Pan-Pan call might be used if an aircraft loses an engine but can still fly safely, or if a ship experiences equipment problems while remaining under control. It tells responders that assistance is needed, but that the situation has not yet become critical.

Few emergency signals are as universally recognizable as SOS. Contrary to popular belief, the letters do not officially stand for "Save Our Ship" or "Save Our Souls." It was adopted in 1906 because SOS is an extremely simple, easy-to-transmit, and unmistakable pattern in Morse code.

SOS remains one of the world's most enduring distress signals, and it's still recognized by rescue organizations all around the globe.

In the NATO phonetic alphabet, each letter is assigned a unique word to eliminate confusion when radio transmissions are distorted by noise or poor reception. If you've ever heard someone spell a name as "Mike Alpha Romeo Yankee," you've encountered the NATO phonetic alphabet.

The system was officially adopted by NATO in the 1950s and is now widely used by militaries, airlines, emergency responders, and many police departments worldwide. Using it greatly reduces the chance of misunderstanding important information over radio.

Roger dates back to the early days of radio communication, when the letter R stood for "received." Before the adoption of the NATO alphabet, the US military used Roger instead of Romeo to represent that letter_._

Although modern communications systems have changed and the US military has fully embraced the use of the NATO alphabet, Roger remains standard aviation terminology, and it's one of the best-known radio acknowledgments in the world. It conveys a very simple but important meaning: "I have received and understood your message."

Although many people assume Roger and Wilco mean the same thing, they actually convey different messages. Wilco is short for "will comply." In other words, it tells the sender not only that the message was received and understood, but that the instruction will be carried out.

Saying both Roger and Wilco is technically redundant in proper radio communication, since complying necessarily implies understanding, but the combination is often heard in movies and television.

In the NATO phonetic alphabet, Tango simply represents the letter T. However, US military personnel have also adopted it as a shorthand when referring to a target or a hostile.

This secondary meaning became widely known through military operations in the twentieth century and has since appeared in countless books, films, and video games in phrases like "We've got one Tango moving north."

Oscar Mike, NATO for the letters O and M, is military shorthand for "On the Move." It's a quick way of reporting that a unit has begun moving toward its objective.

The expression is especially common in the US military and has become more familiar to the general public through documentaries, memoirs, and films. It's finding its way into civilian life, meaning simply "I'm heading out."

Ten-codes were developed during the 1930s to allow for brevity and standardization of message traffic in radio communications. They were widely adopted by US public safety departments and by radio enthusiasts.

While the system is being slowly phased out in favor of plain language communications, many local police, fire, and sheriff departments keep using it, and it is still strongly associated with radio culture by the general public. One of the most famous ten-codes is 10-4, meaning "received and understood."

Hospitals around the world use color-coded announcements to communicate emergencies without causing unnecessary panic among patients and visitors. Perhaps the best known is Code Blue, indicating that a patient is experiencing cardiac or respiratory arrest and requires immediate medical assistance.

While some hospitals use their own custom color codes, Code Blue has become so widely recognized that it now appears frequently in television dramas and everyday conversation whenever someone refers to a life-threatening medical emergency.