Major Depressive Disorder:It refers to a specific type of depressive disorder where individuals experience intense and prolonged periods of sadness and loss of interest.
Persistent Depressive Disorder (Dysthymia): It involves chronic low-grade depression lasting for at least two years, causing ongoing feelings of sadness and hopelessness.
Seasonal Affective Disorder (SAD):SAD is a subtype of depressive disorder that occurs during specific seasons (usually winter) due to reduced exposure to sunlight. Symptoms include low mood, fatigue, and changes in sleep patterns.