In the spirit of better investing and in celebration of the first Worldwide Invest Better Day coming up on Sept. 25, Motley Fool analysts will be answering user- and reader-submitted questions leading up to the big event. "Ask a Fool" anything, and we'll do our best to help you invest better.

In the following video, Fool.com analyst Anand Chokkavelu explains that an income statement is one of the financial statements that investors look at, detailing everything from a company's sales all the way down to its earnings. Comparing income statements across industries, Anand warns that you have to be careful which figures you zero in on, as some will differ wildly depending on the industry. For example, retailers and restaurants have much lower margins than tech providers, which is one of the first things you'll notice if comparing the income statements of companies such as McDonald's (MCD 0.41%)and Cisco(CSCO 0.46%). Watch the following video to learn more, and be sure you're interpreting income statements correctly.

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