Trading firms are companies that buy and sell financial instruments, such as stocks, bonds, and commodities, to make a profit. They often use various strategies, including high-frequency trading and algorithmic trading, to execute trades quickly and efficiently. These firms can operate on behalf of clients or trade for their own accounts. Many trading firms employ teams of analysts and traders who monitor market trends and make informed decisions. They play a crucial role in the financial markets by providing liquidity, which helps ensure that buyers and sellers can execute trades smoothly. Examples of trading firms include Goldman Sachs and Jane Street.