LDF forces arise from temporary opposite charges forming on different molecules. This is because of electron movement within the molecules: as the electrons in one molecule randomly move to one end, causing a dipole (+ve at one end, -ve at the other), the repulsion causes the electrons in a neighbouring molecule to move accordingly. These are the weakest intermolecular force.
http://mrjdfield.edublogs.org/files/2013/11/instantaneous-dipole-instantaneous-induced-dipole-illustration-13ofycm.gifDDF are like LDF in that they are due to dipoles, but in this case the dipoles are permanent, not spontaneous or temporary like in LDF. This is due to electronegativity of elements in molecules. For example, in ICl, Cl is more electronegative than I, so withdraws electron density towards itself, causing a permanent dipole to arise on the molecule, that is, the Cl will posses a small (or delta) -ve charge and the I will posses a small (delta) +ve charge. This leads to the interaction of molecules as they attract each other.
H-Bonding is caused by a delta- positive H on one molecule interacting with a lone pair of electrons on another molecule. These are stronger than the previous two.
http://upload.wikimedia.org/wikipedia/commons/thumb/b/b5/Hydrogen-bonding-in-water-2D.png/800px-Hydrogen-bonding-in-water-2D.pngIonic: forms between a metal and non-metal. The non-metal wants to gain an electron to have a full outer shell. The metal wants to lose an electron to have a full outer shell. So, the metal 'gives' an electron, or more, to the non metal, resulting in two oppositely charged ions, which then attract each other. The larger the charges on the ions, the stronger the bond. Every bond in an ionic compound is ionic i.e. ionic lattices are formed, such as NaCl. These have incredibly high melting points due to the large number of strong ionic bonds which must be broken. Ionic bonding isn't really an intermolecular force, therefore, as it exists between ions, not molecules.
Covalent: two atoms share electrons to obtain a full outer shell. The nuclei in the atoms are mutually and simultaneously attracted to the shared electron pair, resulting in a very strong bond. Again, this isn't an IMF.
Metallic: metal atoms lose electrons when in a metallic structure. This gives a 'sea' of delocalsied electrons and +ve ions. The +ve ions are attracted to the electrons, and vice versa, binding the metal ions together. The more delocalised electrons there are, the stronger the metallic bonds. Not an IMF.
http://www.bbc.co.uk/schools/gcsebitesize/science/images/gcsechem_60.gifI hope this helps. I'ts difficult to give a full explanation of everything, but at least i tried harder than Corribus. Any questions let me know.