Some insects can walk on the surface of water. Which behaviour of water is responsible for this phenomenon?

Due to the surface of the water, light insects are able to walk on the surface of water.

Surface tension also accounts for those with wide feet (generally webbed feet). They have more area on the underside of their feet and if they move fast enough (depending on their weight - the heavier they weigh, the faster they must go to keep on the surface of the water), they are able to "walk on water".