How does osmosis work?

Osmosis can be explained as the passing of water molecules across a partially permeable membrane from an area of high concentration of water molecules to an area of low concentration of water molecules.If water is added to a solution, this will increase the concentration of water molecules whilst decreasing the solute concentration. This will cause water to move out of this area of high concentration of water molecules into an area of low concentration.Alternatively, if solutes (such as sugars or salts) are added to water will decrease the concentration of water molecules within the solution whilst increasing the solute concentration. This will cause water to move into this area of low concentration of water from an area of high concentration.