iShares S&P 100 ETF is an exchange-traded fund or exchange-traded product that provides investors with exposure to large, established U.S. companies included in the S&P 100 Index. It is designed to track or implement a defined investment strategy rather than represent a single operating company. Its performance depends on the underlying holdings or reference instruments, weighting methodology, fund expenses, liquidity, rebalancing rules, and broader market conditions affecting the targeted asset class or theme.