Bipolar disorder is like your brain accelerator being stuck. Mood is amplified and extends far past the comfort level. The mood swings impair the person's ability to function and enjoy life. Everyday living becomes a battle.
It is important to note that bipolar disorder is a treatable medical illness involving changes in behavior, mood, or thought. They are not character flaws or personal weaknesses. They are what a person has--- not who he is.
There are four main types of bipolar:
Bipolar 1- The person with bipolar 1 has had at least one full blown manic episode sometime during his life. That episode has lasted for at least one week or has been severe enough to warrant hospitalization. He may or may not have had depressive episodes. Normally he has. In a major manic episode at least 3 of the following must be present: inflated self esteem or grandiosity, decreased need for sleep, excessive talking or need to talk, racing thoughts, inability to concentrate and easily distracted, significant increase in activity, excessive involvement in risky or potentially self destructive activities. These symptoms must be present for the entire week.
Bipolar 2- The person with bipolar 2 has had at least one major episode of depression during his life. The episode has lasted for at least 2 weeks or is serious enought to warrant hospitalization. In addition he must have had at least one episode of hypomania that last for at least 4 days. Hypomania is a less severe manic state. To qualify for a major depressive episode 5 of the following must be present for at least 2 weeks: depressed mood, diminished interest in activities previously seen as pleasent, disturbance in appetite, sleeping too much or too little, fatigue, feelings of worthlessness or excessive guilt, dimished ability to think clearly or concentrate, thoughts of death or suicide.
Cyclothmia- The cyclothmic person has multiple episodes of depression and mania that don't meet the criteria of the first two diagnoses in terms of either severity or duration. This up and down time must last for at least two years with no more than 2 months of stable time during this period.
Bipolar NOS- The person with this diagnosis has flutuations in mood that do not meet the duration requirements of other diagnoses or not fit their criteria in some other way.
Sometimes people will experience mixed states where they experience both the symptoms of mania and depression at the same time.
The term rapid cycling refers to a person who goes through at least 4 mood episodes in a year. Each episode is a full episode meeting duration and severity requirements.
An extremely good source book to further look at these questions and virtually any other question you have about bipolar disorder is: Bipolar for Dummies by Dr. Candida Fink. We highly recommend it.