Broker

A broker is a firm or platform that executes buy and sell orders for investors in exchange for a fee or commission. A broker is the intermediary between an individual investor and the stock exchange, since retail investors cannot place orders directly on an exchange themselves.

Full-service brokers bundle in research, advice, and account management alongside trade execution, usually at a higher cost. Discount brokers strip that down to just placing orders as cheaply as possible, which is the model most modern online brokerage apps use.