Securities firms are financial institutions that facilitate the buying and selling of financial instruments, such as stocks and bonds. They act as intermediaries between buyers and sellers, helping clients execute trades in various markets. These firms may also provide investment advice and manage portfolios for individuals and institutions. In addition to trading services, securities firms often engage in underwriting, which involves helping companies issue new securities to raise capital. They may also conduct research and analysis to inform investment decisions. Overall, securities firms play a crucial role in the functioning of the financial markets, contributing to liquidity and price discovery.