How are membranes classified according to their permeability?

An impermeable membrane is one through which no substance can pass. Semipermeable membranes are those which only let solvents, such as water, pass through them. Permeable membranes are those which let solvents and solutes, such as ions and molecules, to pass through them. There are also selectively permeable membranes, which are membranes that, in addition to allowing the passage of solvents, let specific solutes pass through while blocking others.