Bipolar disorder is known to occur on a spectrum, says Wright. According to the Diagnostic Statistical Manual of Mental Disorders (DSM-5), there are four main types:

* Bipolar I Disorder: When you have a manic or mixed episode that lasts at least a week, or is severe enough that it requires immediate hospitalization. Plus, this is usually accompanied by depressive episodes.

* Bipolar II Disorder: When you experience both depressive episodes and hypomanic episodes, but without any full manic or mixed episodes.

* Bipolar Disorder Not Otherwise Specified (BP-NOS): When you have symptoms of bipolar disorder that don't technically meet the criteria for any specific type.

* Cyclothymia: When you have hypomanic and depressive symptoms that don't quite fit the criteria for mania, hypomania, or depressive episodes (and it lasts on and off for at least two years).

There's also rapid-cycling bipolar disorder, where you have four or more episodes in a year. You can find more info from the National Institutes of Mental Health (NIMH) here.