Each of the tiny holes leads to a large tube called the trachae. The larger tube branches off into many more tiny tubes that go throghout the body. This is very different from the way we humans breathe. We have lungs. Insects also breathe differently than arachnids.
Arachnids have book lungs.
These are not very effective. I think they have lungs. I think that because when my pet grasshopper breathes in and out you can see his abdomen expand and contract as like humans do. This is different from humans or mammals because the insects' lungs are a lot smaller than a mammmals and they breathe through holes in their abdomen. That is really neat.