Is an appeal the same as????

Hi, just wondering if an appeal is the same thing as a re-consideration? My insurance company denied me gastric bypass surgery, because they said it is not medically necessary. They have requested more information from my PCP, such as having me tested for chronic pulmonary disease, and a chest x-ray. Now, it is at the reconsideration stage. When I was denied, I sent in an appeal. This is why I am asking if the two are the same? thanks for all the help!!