nline/discount brokers are basically just order-takers and provide the least expensive way to start investing since there is typically no office to visit and no certified financial planners or advisors to assist you. The only interaction with an online broker is over the phone or via the Internet. Cost is usually based on a per-transaction or per-share basis, but many have commission-free trades. They typically allow you to open an account with very little money. An account with an online broker allows you to buy and sell stocks/options instantly with just a few clicks.