A broker is an intermediary who executes buy and sell orders for clients. You want to buy 100 shares of a company. The broker places the order on the exchange and handles the paperwork. For this service, the broker charges a commission or a fee. Brokers exist in stocks, bonds, commodities, real estate, and insurance.

Types vary. Full-service brokers offer advice, research, and personal attention. They charge higher fees. Discount brokers execute trades at low cost but offer little guidance. Online brokers have made trading accessible to anyone with a phone and a bank account. Robo-advisors use algorithms to build and manage portfolios automatically. Each model serves a different kind of client.

The industry has changed dramatically. Commissions that once cost hundreds of dollars are now often zero. Revenue comes from other sources: payment for order flow, margin lending, and premium services. That shift has raised questions about conflicts of interest. A broker that routes orders to a particular market maker may not be getting the best price for the client. Regulators watch closely. Choosing a broker involves more than looking at the fee schedule.

Common types

• Full-service broker
• Discount broker
• Online broker
• Robo-advisor
• Insurance and real estate brokers