The SEC, or Securities and Exchange Commission, is an independent federal agency in the United States responsible for regulating and overseeing the securities markets. It was established by Congress in 1934 in response to the financial crash of 1929 and the Great Depression to restore investor confidence and promote fair, orderly, and efficient markets. The main functions of the SEC include:

• Protecting investors by ensuring companies provide accurate and transparent information so investors can make informed decisions.
• Regulating securities markets and overseeing stock exchanges, brokers, investment advisors, and other market participants.
• Enforcing securities laws to prevent fraud, insider trading, market manipulation, and other misconduct.
• Facilitating capital formation by allowing companies to raise funds through public offerings.
• Providing a platform for companies to disclose financial information regularly via filings such as quarterly and annual reports.

The SEC is governed by five commissioners appointed by the President and confirmed by the Senate, with a rule that no more than three commissioners belong to the same political party to maintain independence and balance. It is organized into five main divisions handling corporate finance, investment management, enforcement, economic analysis, and market regulation. Overall, the SEC's mission is to protect investors, maintain fair and efficient markets, and facilitate capital formation in the U.S. securities markets. This ensures transparency, honesty, and trust in the financial system for the benefit of the economy and investors.