Van Der Waals Force

Van Der Waals force is a weak attractive force between atoms or nonpolar molecules caused by an instantaneous dipole moment of one atom or molecule that induces a similar temporary dipole moment in adjacent atoms or molecules.

In simple words, Van Der Waals forces are short range electro magentic forces that attract dust to surfaces, you may have noticed that your television screen gets dusty very quickly this is partly due to van der waals forces.