If look to the top of the topic list here there is a post on what bipolar is. It is pretty informative and gives you a good understanding of the textbook definitions.
You are asking one of the most loaded questions in the world "what is it like?"
There is no real simple answer for that...it is kind of like being left handed. You know, it just is. If you take the time and read more on this board (and others) you will get a feeling for what living with bipolar is like.
For your benefit:
Considered the classic form of the illness, bipolar I causes recurrent episodes of mania and depression. The depression may last for a short time or for months. You may then go back to feeling normal for a time, or you may go right into a manic episode.
If you have bipolar II, you will experience depression just as in bipolar I. However, the episodes of mania are less severe (hypomania). Bipolar II is more common in women. People with bipolar II have more depressive than hypomanic episodes.
Rapid-cycling bipolar disorder.
If you have rapid-cycling bipolar disorder, you will experience at least four episodes of depression, mania, or both within a 12-month period. You may go directly from an episode of depression to an episode of mania, or you may have a short time lapse between the two moods. The mood swings are the same as with other types of bipolar, but the frequency of mood swings distinguishes rapid-cycling bipolar disorder from the other subtypes.
There are other bits that I could add, but this covers the "classics" of bipolar.
Me, I fit into BP I...but it doesn't end there...yes, since I was fortunate enough to experience a psychotic episode during a mania I am also diagnosed with Schizo-Affective Disorder (but that is a different story). I was diagnosed with BP I after a butt load of years of being diagnosed with "major depression" and other starter diagnoses.
You ask about medications...well that is an interesting subject that you will find a myriad of opinions on. Personally, I have taken anti-depressants, though they were effective at the time, they are no longer needed. Now I take a mood stabilizer (Depakote/Epival) which is pretty much self explanatory. I also have Seroquel and Zyprexa for the times when I get manic and "the voices" come creeping back.
If there is one thing you will learn about most of these drugs, it is that they do affect your bodies metabolism. For most of us, with most of the drugs, that means some weight gain. There are some drugs that are worse than others...Zyprexa...you gain five pounds just picking up the prescription. There are a few 'weight neutral' or 'weight negative' drugs available, but they do have their side effects as well (ie. Topamax...instant stupidity and kidney stones).
If you need info on drugs try:
Hope this helps,