Ionic bonds are typically weak, non-directional primary bonds between atoms, where one cation donates its valence electrons to one or more anions. They often occur between a metal and a non-metal such as table salt (NaCl). Materials made from ionic bonds tend to be more ductile than covalent ones but are still more brittle than metallic bonded ones.
Covalent bonding is a strong type of primary bond that is highly directional as the atoms share their valence electrons. This makes the material less ductile. An example of this is carbon-carbon bonds in diamond.