Question About Armor Piercing

[Zoob]

I'm a little curious as to what exactly the armor piercing firing mode of most weapons really does. I often switch to it if I'm shooting at a MAX unit or a Vehicle. Then use my regular fire to take down infantry.

However I really don't see a big difference when I forget to switch back. Can anyone tell me the advantages of armor piercing mode? does it only damage an enemies armor? If so does regular firing mode do little damage to armor and more to health?


Thanks!