A wildfire is a large, uncontrolled fire that spreads rapidly through forests, grasslands, or brush. Unlike a campfire that stays in one spot, a wildfire can race across miles of land, consuming everything flammable in its path: trees, shrubs, grass, and sometimes even buildings.

Wildfires often start from lightning strikes during dry weather, though careless humans cause many too: an abandoned campfire, a cigarette tossed from a car, or sparks from equipment. Once started, wind pushes the flames forward while dry conditions provide fuel. A wildfire can move faster than a person can run, leaping from treetop to treetop or racing along the ground through dry grass.

Firefighters battle wildfires using planes that drop water or fire retardant (a special chemical that helps stop flames from spreading), and by cutting firebreaks: cleared strips of land with nothing to burn, which can stop a fire's advance. Some wildfires burn for weeks or months before crews fully contain them.

While devastating, wildfires play a natural role in many ecosystems. Certain pine cones only release their seeds after a fire, and some plants grow back stronger after burning. Still, as more people build homes near forests and climate patterns shift, wildfires have become more frequent and destructive.

The phrase spread like wildfire describes anything that moves or becomes popular extremely quickly, like a rumor spreading through school or a new video game everyone suddenly wants to play.