What is depression

Most people say that they are depressed. When in actuality, they just feel sad. Depression is a serious matter. It affects your life in more ways than one. Depressed people cannot function on a day to day basis, they have trouble communicating, their sadness consumes their life. They can't think of anything but how miserable they are. Depression, I think is caused by a sudden change in your life/routine. Losing a loved one perhaps can spiral into uncontrollable sadness and loss.