MMORPG.com EVE Online Correpondent Joanie Spalletta writes this informative guide comparing Armor and Shield tanking in CCP's EVE Online.
To keep your ship alive in EVE, you must have a tank. You can do this two different ways. You can shield tank, or you can armor tank. To decide which one is right for you, take a look at your character’s skills. The two categories you’re going to want to look at are Engineering and Mechanics. If you have more skill points in Engineering, shield tanking is probably best for you. If you have more skill points in Mechanics, go with armor tanking.