Decoding language

10 punctuation secrets your teachers never told you

Image: Samuel Ramos

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.

The truth about your brain

You won’t believe what happens in your brain while you sleep

Image: Milad Fakurian

Your brain is one of the most powerful and mysterious organs in your body. It controls everything from your thoughts to your emotions and even processes information at lightning speed. But how much do you really know about it? Some long-believed myths about the brain have been debunked, while other surprising facts reveal just how incredible this organ truly is. Get ready to be amazed by these fascinating brain facts!

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You’ve probably heard this one before, but it’s completely false! While it’s true that not all parts of the brain fire at the same time, imaging studies show that most regions are active throughout the day, even when we sleep.

Your brain is constantly working, controlling bodily functions and emotions, and processing information. So next time someone says you’re only using 10% of your brain, you can confidently tell them that’s just a myth!

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Here’s a weird fact: While your brain processes pain signals from the rest of your body, it has no pain receptors of its own. This is why surgeons can perform brain surgery on conscious patients without causing them pain.

However, the membranes and tissues surrounding the brain do have pain receptors, which is why headaches and brain injuries can be so excruciating.

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How come we have headaches if the brain has no pain receptors? Well, that’s because headaches are triggered by chemical activity in the brain, changes in nerves and blood vessels, and even fluctuating serotonin levels.

In some cases, hormones like estrogen can also play a role, which explains why migraines are more common in women.

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Dreams are proof that your brain never rests! (Warning: this fact can make you feel exhausted.) While you sleep, your limbic system, that is, the part of the brain that deals with emotions, becomes especially active, which is why dreams often feel so intense.

On average, humans experience four to seven dreams per night, even if we don’t always remember them. And what about that scary nightmare about falling? Well, you can thank your amygdala, the brain’s fear center, for that one.

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Have you ever walked into a room and instantly forgotten what you were after? That’s because short-term memory only lasts about 20-30 seconds! That’s not enough!

Your brain holds a limited amount of information in its active state before deciding whether to store it or discard it. Ironically, we can’t really choose what makes the cut, but we do hope these facts stay with you!

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That sharp, icy pain when you eat something too cold? It’s your brain’s way of telling you to slow down! Officially called sphenopalatine ganglioneuralgia, a brain freeze happens when cold food or drinks rapidly chill the blood vessels in your throat, causing them to constrict and then rapidly expand. This sends pain signals to your brain, warning you of the sudden temperature shift. It’s annoying, but it’s actually your body trying to protect itself!

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You didn’t need us to tell you, but let’s look at the details: The average person has between 12,000 and 60,000 thoughts per day. What’s even more interesting? 95% of those thoughts are the same ones you had yesterday. Is that not surprising enough? Hear this out: 80% of them tend to be negative. That’s because our brains are wired for survival, constantly analyzing risks and potential dangers.

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Even though it only makes up about 2% of your body weight, your brain employs a major quantity of energy! It consumes 20% of your oxygen and blood supply, making it one of the most demanding organs in your body.

If your brain goes without oxygen for just five minutes, brain cells start dying, leading to irreversible damage. This is why deep breathing and cardiovascular exercise are great for brain health!

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Do you know that feeling when you hit the back of your head and see stars? That’s because your occipital lobe, which controls vision, is located at the back of your brain. If you get hit there, your brain momentarily misfires, causing flashes of light.

Interestingly, your brain processes vision on the opposite side; while your right brain controls your left eye, your left brain controls your right eye. It’s one of the many ways the brain operates in a complex way.

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Believe it or not, your brain generates between 12 and 25 watts of electricity when you’re awake. If you can’t really grasp how powerful that is, check this out: It’s enough to power a small light bulb! Your brain’s electrical activity is what allows neurons to send signals at speeds of up to 260 miles per hour.

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Your brain may be the fattiest organ in your body, consisting of at least 60% fat! This is why consuming healthy fats, like omega-3s and omega-6s present in fish, for example, is essential for brain health.

Healthy fats stabilize brain cell walls, reduce inflammation, and support cognitive function. So go ahead and enjoy that avocado toast, it’s food for your brain!

Image: Robina Weermeijer

It’s not just your memory that fades over time; the brain itself physically shrinks as one gets older. It continues developing until your late 40s, but after that, it slowly decreases in size.

Now, size doesn’t equal intelligence, so a smaller brain doesn’t necessarily mean a less capable one. Staying mentally active, exercising, and eating brain-boosting foods can help keep it in top shape!

Image: Lisa Yount

We often think of cholesterol as bad, but your brain actually depends on it! In fact, 25% of your body’s cholesterol is stored in your brain, where it helps with learning and memory. However, unlike other organs, the brain can’t absorb cholesterol from the blood, it has to produce its own. So, while too much cholesterol in the body can be harmful, the right amount is vital for brain function. At least you can use that as an excuse to get that burger!