For the active trader, execution speed and fill price are very important. I won’t get too in depth here but I have tested many of these brokers and there can be noticeable differences in trade execution times and quality. For the majority of investors, saving a penny per share on a 100 shares order isn’t the end of the world, but for active traders it is something to look into. To understand Order Execution, read this guide.
When you buy a stock, you should have a good reason for doing so and an expectation of what the price will do if the reason is valid. At the same time, you should establish the point at which you will liquidate your holdings, especially if your reason is proven invalid or if the stock doesn’t react as expected when your expectation has been met. In other words, have an exit strategy before you buy the security and execute that strategy unemotionally.
A broker is simply a licensed person through whom you can buy and sell these stocks. When you use an online platform, it essentially acts as an online broker. If someone wants to buy any product, he can contact a brokerage service. They would place an order and let him know the market price of the product. If the investor is interested, they would include a commission for themselves and process the order forward. If the user wishes to buy stock, the broker would forward his order to a stock exchange, which would approximately take 3 days to complete including the money exchange between the broker and the investor.