Bipolar+mood+disorder

What is Bipolar Disorder/Manic Depression??
It is a brain illness that cause unusual, dramatic shift in person's mood, behavior and energy. The symptoms of Bipolar Disorder are severe because it can result to poor job and school performance, damaged relationship and even suicide.Bipolar Disorder can be treated, people with Bipolar Disorder can also owned a normal lives. About 2.6 percent of the population (age 18 or above) in America have Bipolar Disorder

What are the symptoms of Bipolar Disorder?
Bipolar Disorder is a mental sickness which people can be overly "high"(happy/excited) and turn to overly "low"(sad /hopeless) What types is there? What is the cause of Bipolar Disorder