Dispersion force is a force created due to the fact that electrons are not equally distributed around the nucleus at all times. As a result of this a negative charge is created in the area there are a relatively larger number of electrons as compared to the area with a smaller number of electrons. This distribution of charge is one that changes constantly with time. The resultant force between particles, atoms or molecules, is known as dispersion force. Dispersion forces are present between particles that make up all types of substances. Methanol molecules also have dispersion forces acting between them.
Hydrogen bonding takes place between molecules of substances that have a hydrogen atom and another electronegative atom. In molecules of methanol there are covalent bonds between the carbon and hydrogen atoms but the carbon atoms being more electronegative attract the shared electrons more strongly that the hydrogen atom. This results in hydrogen acquiring a positive charge and carbon acquiring a negative charge. Oppositely charged atoms of different molecules are attracted to each other which is known as hydrogen bonding. The cohesive forces between molecules of methanol include the dispersion force as well as hydrogen bonding.