So basically, the passive diffusion of water via a semipermeable membrane is known as osmosis. And in osmosis, water always travels from a high water concentration to a low water concentration or equivalently from a low solved concentration to a high solub concentration. These two statements are exactly equivalent. And to see what we mean, let's take a look at the following three conditions. So, let's discuss the Hypotonic solution, the hypertonic solution and the isotonic solution. In the Hypotonic solution we have a very high concentration of solutes inside the cell, much higher than the solute concentration outside the cell.