Science
26 explanations and counting.
What is the placebo effect?
Sometimes a sugar pill that does nothing can make people genuinely feel better. That's not self-delusion — it's one of the most powerful and least understood phenomena in medicine.
What is a hormone?
Your body doesn't use wires to send messages — it uses chemicals released into the blood. Hormones are those chemical messages, and they control almost everything about how you feel and function.
How does nuclear fusion work?
It's the same process that powers the Sun — smashing atoms together to release enormous energy. Scientists have been trying to do it on Earth for 70 years, and they're finally getting close.
What is CRISPR?
Scientists can now edit the genetic code inside living cells like editing a document — cutting out errors and replacing them with working instructions. CRISPR is the tool that made it possible.
What is the gut microbiome?
Your gut is home to trillions of bacteria, viruses, and fungi that affect your digestion, immune system, and even your mood. Far from being harmful, most of them are essential.
How do GLP-1 drugs (like Ozempic) work?
Ozempic and drugs like it have changed how millions of people think about weight. But how does a weekly injection tell your brain you're not hungry?
What causes allergies?
Your immune system treats peanuts like a mortal threat. Pollen makes you sneeze for weeks. Why does the same system that defends you sometimes attack harmless things?
What is the immune system?
Your body is under constant attack from bacteria, viruses, and other threats. The immune system is the remarkable defence network that fights them off — usually without you noticing.
How do magnets work?
Magnets can attract metal through a wall without touching it. The explanation involves spinning electrons — and it's genuinely weird.
Why do we age?
Ageing isn't just wear and tear — it's written into your biology at a cellular level. Scientists now understand quite a lot about why it happens.
What is a chemical reaction?
Chemistry isn't just something that happens in labs. It's happening inside your body right now, in your food, in the air. Here's what a chemical reaction actually is.
How does the brain work?
The most complex object known to exist in the universe weighs about 1.4kg and sits in your skull. Here's a beginner's guide to the thing doing the reading right now.
What causes the Northern Lights?
Curtains of green, purple, and pink light dancing across the night sky. It's one of the most spectacular things nature produces — and it's caused by the Sun bombarding Earth.
What are atoms made of?
You and everything around you is made of atoms — and atoms themselves are made of even smaller things. Here's how deep the rabbit hole goes.
How does sound travel?
Sound isn't a thing — it's a movement. Understanding how vibrations travel through air (and other materials) explains everything from music to thunder.
Why do we need sleep?
You spend about a third of your life unconscious. Sleep isn't wasted time — it's when some of the most important work your body does actually happens.
How does the human eye work?
Your eye captures millions of data points every second and sends them to your brain as electrical signals. Here's the remarkable mechanics behind it.
What is evolution?
Every living thing on Earth — from oak trees to blue whales to you — is related. Here's the process that produced all that extraordinary variety.
What is gravity?
It keeps you on the ground, holds the Moon in orbit, and shapes the entire universe. But what actually <em>is</em> it?
Why do we have seasons?
It's nothing to do with how far Earth is from the Sun. It's all about tilt — and the answer is stranger than you'd think.
How does electricity work?
You use it every single day. But what actually is electricity, and how does it get from a power station to your phone charger?
What causes thunder and lightning?
A thunderstorm is basically a massive static electricity machine in the sky. Here's exactly what's happening up there.
What is DNA?
Inside almost every cell in your body is a set of instructions so long it would fill 3,000 books. That's DNA — and it basically built you.
Why do we dream?
Every night your brain puts on a private cinema just for you. Scientists still aren't totally sure why — but they have some pretty fascinating ideas.
Why is the sky blue?
The sun's light is actually all the colours at once. So why does only the blue bit reach your eyes? Here's the weird truth.
How do vaccines work?
Vaccines train your immune system to fight diseases before you ever get ill. It's like a fire drill for your body.