When choosing an investment, you should look for a few key factors including the potential for growth, how that investment fits your financial goals, the level of risk you are comfortable taking, and how long you plan to invest. For instance, if you're considering a stock that costs $50 and you believe it will grow to $100 over 5 years, that suggests a potential return of 100% over that period. However, you should also consider the risk of price fluctuations along the way.

Investment Horizon refers to the length of time you expect to hold an investment before taking the money out. It’s an essential concept because it influences your investment choices; for example, a longer investment horizon may allow you to take on more risk, as you have more time to recover from potential losses.