How do macrophages protect your body from infection?

The question is asking to state how do macrophages protect your body from infection, base on my research and further understanding, I would say that the answer would be that it conjures images of a hungry white blood cells gobbling invading bacteria. I hope you are satisfied with my answer 

Maybe if you put away all your electronics and lock them with a key and give the key to some one you trust like your parents for about a month to stop the process