A waterslide is a slippery, wet slide built for sliding down at swimming pools, water parks, or backyard play areas. Water flows continuously down the slide's surface, making it fast and slick. You might climb stairs to reach the top, then whoosh down in seconds, splashing into a pool at the bottom.

Waterslides come in many varieties. Some are straight and simple, perfect for younger kids. Others twist and turn like serpents, with enclosed tubes that make you feel like you're shooting through a tunnel. The tallest waterslides at water parks can be several stories high, giving riders thrilling speeds before they splash down.

The flowing water serves two purposes: it makes the slide slippery enough for a fast ride, and it keeps the surface cool even on hot summer days. Without water, the friction would slow you down, and the slide would feel uncomfortably hot.

Some people use waterslide as a verb, like saying they spent the afternoon watersliding at the pool. The pure joy of climbing up and sliding down again and again makes waterslides one of summer's great pleasures.