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Inflation is the steady rise in the general level of prices, which means each coin and banknote buys a little less over time. Learn how it is measured, what causes it, why central banks aim for about 2 percent, and what happens when prices spiral out of control.

Brainabra·10/31/2026

A stock market is where people buy and sell small pieces of ownership in companies. Learn how shares get their prices, how exchanges began in coffee houses and under a tree, and what famous crashes taught the world.

Brainabra·10/31/2026

Bitcoin was the first currency to run without a bank or government in charge. Learn who invented it, how mining and the blockchain work, why only 21 million coins will ever exist, and why it remains so hotly debated.

Brainabra·10/31/2026

A vaccine teaches the immune system to recognize a germ before the real infection arrives. Discover how vaccines work, how they were invented, the main types used today and how they helped wipe smallpox off the planet.

Brainabra·10/31/2026

Your body is defended day and night by barriers, roaming cells and molecules that learn. Discover how innate and adaptive immunity work together, why vaccines are so effective, and what happens when the defenders make mistakes.

Brainabra·10/31/2026

Penicillin began as a lucky accident in a London lab and became the medicine that changed how we fight infection. Discover how it was found, how it kills bacteria, and why resistance now threatens its power.

Brainabra·10/31/2026

Sleep looks like rest, but the brain is busy all night, cycling through stages that store memories, clear waste and reset the body. Here is how sleep works, why we need it and what happens when we go without.

Brainabra·10/31/2026