Buying shares and buying stocks are the same thing. When you invest in a publicly traded company or an exchange-traded fund (ETF), you do so by buying shares of stock in that company or fund. The stocks you buy might decline in value. That’s why it’s important to have an investment strategy that includes a plan for weathering unfavorable market conditions, such as through diversification. On the other hand, you’ll get closer to your investment objectives if your stock valuation increases. Earnings you make from stocks are called capital gains and are subject to taxes.