About a million americans will develop skin cancer this year. Skin cancer is the most prevalent of all cancers, and it's increasingly on the rise. There are millions of tiny cells that make up the human body. There are different kinds of cells, but they all make new cells by a process that involves dividing in half. This is how old cells are replaced with strong new cells. When a cells divides and doesn't do the job that it was intended to do for the body, and then it continues to divide and makes more of these "useless" cells, and these cells continue to collect, it is called a tumor. There are two types of tumors: benign and malignant. The cells in a benign tumor can "crowd out" healthy cells, even though they can not spread to other, and healthier, parts of the body (Ingraham 447). However, a malignant tumor is cancer. A malignant tumor can also "crowd out " the healthy cells around it, but in addition to thatt it can spread to other parts of the body and take over the healthy cells in different areas of the body. Skin cancer is a disease in which cancer cells are found in the outer layers of skin. The skin has two main layers and several kinds of cells. The top layer is the epidermis and it is the layer that is shed most frequently. The inner layer is called the dermis and is thicker and contains blood vessels, nerves, hair follicles and sweat glands (Seely Stephens Tate 145). Cancer spreads by a group of cells or a single cell that breaks away from the tumor and moves to other parts of the body. Once there, it'll divide and start tumors, made of malignant cells, like the ones that mad up the first tumor (Ingraham 447). When this happens it is called metastic cancer. Metastatic cancer is defined as the transfer of disease from one part of the body to another, as in certain types of cancer (Funk & Wagnalls Dictionary 408.) . With many cancers, the usual first step in prevention is that the affected ...