The most popular of the capitalizations is the large cap stocks, which are the Apples and Facebooks of the world. These companies are the ones that many people invest and trade in because they are most familiar with their brand and what they do. If you look at the Dow Jones Industrial Average, these are all large cap stocks. The S&P 500 is also made up of some large cap stocks.
Taking the next step, there is the mid cap stocks, which many are companies that we may have heard of but are unsure what they do. Mid cap stocks are still solid companies and many have been around for quite some time, but it also could include some newer companies with stock prices that are lower. People who are willing to take on a little more risk for potentially more return on their investment, the mid cap level is the place to look.
Then there is small and micro cap stocks, which are companies who are very small compared and have low stock prices typically. These companies are smaller and typically do not have the reputation of being a sturdy investment. However, the potential for serious returns is there, but the risk level here is the greatest at this level looking at the capitalization levels.
When you are building a portfolio or looking at funds, it is important to stop and think how much of each level you want in your portfolio. Someone who is just starting out may be more apt to look at the mid and small cap area because it can generate greater returns and the risk tolerance is greater when first starting out. If it is towards the end of your investing life, you may want to stick with large cap stocks as these are the most likely to perform well.
Be sure to take a look at your current portfolio holdings and see how they are allocated among the three different capitalization levels and see if you are comfortable with where they line up. If you are unable to take the time, you may be interested in putting your money in mutual funds that cover these three areas as they can give you sector exposure without the company specific risk. Take the time and understand each area and see if you could reallocate your portfolio to limit risk and grow returns.