It is an image of a man standing at the edge of a ledge next to water. He is bent over with his hands out in front of him towards the water. The image has a slash through the man seeming to mean no diving into the water.
This No Diving icon is made in Material Design style
developed by Google. This style is based on extremely simplified shapes, thin two-pixel lines, and is optimized for 24x24 px. Unlike other vector icon packs that have merely hundreds of icons, this icon pack contains 5,700 icons, all in the same style and quality.