Annual Report
  
How'd ya do this year? Financially speaking...
That's really all an annual report is. A report card with dollar signs. Generally, in public companies, an annual report covers the three legs on the stool of financial reporting: an Income Statement, a Cash Flow Statement and a Balance Sheet.
If we're talking about a public company in the U.S., investors already know much of the information by the time the annual report comes out. That's because the company puts out regular quarterly earnings statements. However, the annual report is often more detailed. There's rarely information that will move the stock (though every once in a while, the company tries to sneak something in), but real investing nerds like to dive into the minutiae and then ask questions on conference calls that make Elon Musk yell at them.