Identify what the electron dot diagram tells you about bonding

The electron dot diagram tells us about how many electrons are being shared between atoms. Also, the number of valence electron to be shared corresponds to the group number the element belongs. Say for example H2O, hydrogen has one valence electron and oxygen has two valence electrons.

The electron dot diagram, like the dot and cross diagram shows us the bonding electrons in a compound, the nature of the bond, that is if it is shared pair or exchanged to form covalent or ionic bond respectively, further more it also shows non bonding valance electrons as well.