Mood swings are sudden and intense changes in a person's emotional state. They can range from feelings of happiness and excitement to sadness or irritability, often without a clear reason. These fluctuations can occur in anyone but are commonly associated with conditions like bipolar disorder, depression, or anxiety. Various factors can trigger mood swings, including stress, hormonal changes, lack of sleep, or certain medications. While occasional mood changes are normal, frequent or severe swings may indicate an underlying issue that could benefit from professional evaluation and support.