Stock brokers are the people that help you trade stocks. They can be real life people or online programs. Basically they do their best to make sure that your order is filled. If you were to request 50 shares in Apple inc, the stock broker would look for the best deal they could find and then finish the transaction. Personally, I prefer online stock brokers. They are cheaper and quicker to use, although they can’t offer good advice like real stock brokers can.
Thats all for now, Ben