Hygiene is the practice of keeping yourself and your surroundings clean to stay healthy and prevent disease. When you wash your hands before eating, brush your teeth twice a day, or take a shower, you're practicing good hygiene. These simple habits help remove germs, bacteria, and dirt that can make you sick.

For thousands of years, people have understood that cleanliness helps prevent illness. In the 1800s, doctors discovered that something as simple as washing hands between patients could save lives. Today we know that good hygiene stops germs from spreading, which is why schools may close during flu outbreaks and why surgeons scrub their hands so carefully.

Hygiene includes both personal cleanliness and keeping spaces clean. A kitchen with good hygiene has clean counters and properly stored food. A hospital with excellent hygiene sterilizes equipment and sanitizes rooms. Poor hygiene, on the other hand, creates conditions where disease spreads easily.

The word can also describe cleanliness in a broader sense. Someone might talk about sleep hygiene (habits that help you sleep well) or mental hygiene (practices that keep your mind healthy). In all these cases, hygiene means the regular practices that maintain health and prevent problems before they start.