Cohesion and Adhesion are 2 properties of water.
Cohesion is when water molecules are attracted to other water molecules. This is because there is an attractive force between the positive and negative parts of the water molecules.
Adhesion is when water is attracted to other materials.
Surface tension describes the cohesion of water molecules on the very surface of the water. When the molecules are attracted to each other they are held together. This allows for things to float on the surface of water. If they are light enough or are buoyant the surface tension of the water will hold them up.