Bipolar affective disorder, aka manic depression or just bipolar disorder, is a condition that causes severe mood swings. The mood swings vary from excitement and elation known as mania, to depression and despair. Bipolar affective disorder affects your mood and behaviour. If you have it, you will experience extremes of emotion, from excessive energy and elation to depression and suicidal thoughts. Your moods will swing between the 2 extremes.
Attribution: BUPA