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Depending on your goals, investing in individual stocks may be more trouble than it’s worth. Choosing index funds in a specific sector can provide your portfolio with the tilt you want, but with fewer dramatic swings. There are three criteria that can be leveraged to help guide fund choice. The most discussed is “expense ratio,” where lower means fewer fees to you. The second is the number of stocks in the fund. The higher the number, the more diverse the fund. Just as important is “total assets” under management. The more assets, the more other people also agree this is a great fund. When comparing two mutual funds, I’ll line up these three criteria for funds in the same category to make an informed decision.
Because of the web today, all online brokers invest heavily into account security. SSL websites (look for “https” at the beginning any URL) are used by most brokers and some are now even offering two-factor authentication (using your phone to confirm a code before logging in). Just like shopping online and choosing a trustworthy website to purchase from, the best bet is to choose a well-known, established broker for your portfolio.
TD Ameritrade offers a full portfolio of investment products, which include not only traditional stocks and bonds, but also futures, Forex, foreign ADRs, and even IPOs for some accounts. Fees are near average for the industry, while there’s commission-free trading for some investments, but you still face high rates for broker-assisted trades. Ameritrade does not assess fees on inactive accounts or partial transfers, but there is a $75 charge for every full transfer you make.
In the professional world, one of the key concepts is diversification. Harry Markowitz is a Nobel prize winning economist and one of his major discoveries was that adding new asset classes can dramatically alter the overall risk profile of a portfolio. His finding was that a portfolio that contained very low risk assets would normally benefit from lower volatility and higher returns if a higher risk asset was added. This is due to the likely lack of correlation between high and low risk asset classes.

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.