external image james-bondPic.jpg

"Bonds" "Electron Bonds"Ionic bonding
An ionic bond is created when two elements transfer electrons to create ions that attract each other. Ionic bonds are a made between a non-metal and a metal. Sodium chloride is a great example of an ionic bond. It is created when the elements sodium and chlorine combine.
external image Ionic_bonding_animation.gif

GIF from wikipedia http://upload.wikimedia.org/wikipedia/commons/7/75/Ionic_bonding_animation.gif
Covalent Bonds
Covalent bonds are created when electrons are shared between atoms. Covalent bonds are created between a non-metal and a non-metal. H2 is an example of a covalent bond. These are the strongest type of bond. Covalent bonds are polar because electrons are shared unequally, This causes one end of the molecule to have a slightly negative charge and the other to have a slightly positive charge.

Polarity of bonds
Polarity refers to a separation of electric charge leading to a molecule having an electric dipole. Polar molecules can bond together due to dipole–dipole intermolecular forces between one molecule (or part of a large molecule) with asymmetrical charge distribution and another molecule also with asymmetrical charge distribution. Molecular polarity is dependent on the difference in electronegativity between atoms in a compound and the asymmetry of the compound's structure. For example, a molecule of water is polar because of the unequal sharing of its electrons in a "bent" structure, whereas methane is considered non-polar because the carbon shares the electrons with the hydrogen atoms uniformly. Polarity underlies a number of physical properties including surface tension, solubility, and melting- and boiling-points.
From http://en.wikipedia.org/wiki/Chemical_polarity


Types of bonds are important because they tell how different chemicals bond with each other. Knowing how these work can help you get to a desired result.