Gold can be traded in several ways, including physical bullion, certificates, futures, ETFs, stocks, and options. Physical gold allows investors to directly own the metal but comes with security and storage costs. Gold certificates were paper receipts for gold but now are collector's items. Gold futures are contracts for future delivery at a set price and offer leverage. Gold ETFs provide exposure through a basket of assets but involve fees. Gold stocks offer exposure to gold prices but their value depends on other factors. Gold options give the right to buy or sell gold at a future date and price. Overall, the document discusses various vehicles for investing and trading in gold.