TQQQ is a leveraged exchange-traded fund (ETF) that aims to deliver three times the daily performance of the NASDAQ-100 Index. This means that if the NASDAQ-100 rises by 1% on a given day, TQQQ is designed to increase by 3%, and vice versa. However, due to the effects of compounding, its long-term performance can significantly deviate from three times the index's return, especially in volatile markets. TQQQ is considered a high-risk, high-reward investment and is generally suitable for sophisticated investors with a short-term trading horizon who understand the risks associated with leveraged ETFs.