The US stock market is a financial marketplace where publicly traded companies sell shares of their ownership to investors. The US stock market is one of the largest and most important in the world, with major stock exchanges including the New York Stock Exchange (NYSE) and the Nasdaq.

Investors can buy and sell stocks through brokerage firms, either online or in person, and can invest in a range of different securities including stocks, bonds, exchange-traded funds (ETFs), and mutual funds. The stock market is influenced by a range of factors, including economic data, company earnings reports, geopolitical events, and investor sentiment.

The performance of the US stock market is often used as an indicator of the health of the overall economy, and it can have a significant impact on both individual investors and the wider financial system.