An avalanche is a sudden and fast-moving flow of snow, ice, and debris down a mountain slope. It occurs when a layer of snow becomes unstable and breaks loose, often triggered by factors like heavy snowfall, warming temperatures, or human activity. Avalanches can vary in size and speed, posing significant risks to anyone in their path. There are different types of avalanches, including slab avalanches, which involve a cohesive layer of snow breaking away, and loose snow avalanches, which consist of loose, powdery snow. Understanding the conditions that lead to avalanches is crucial for safety in mountainous areas, especially for skiers and snowboarders.