St. John's Wort is a flowering plant known scientifically as Hypericum perforatum. It is commonly used in herbal medicine, particularly for its potential effects on mood and mental health. The plant contains compounds that may help alleviate symptoms of mild to moderate depression. Traditionally, St. John's Wort has been used for centuries in various cultures. It is often available in forms such as capsules, teas, and extracts. While some studies suggest it may be effective, it can interact with certain medications, so it's important to consult a healthcare professional before use.