A continuous life of an entity can be divided into measured periods of time, for which financial statements are prepared.
U.S. companies are required to file quarterly (10-Q) and annual (10-K) financial reports. These reports will be discussed in full detail in Chapters 3 and 4.
Typically one calendar year represents one accounting year (usually referred to as a fiscal year) for a company. Be aware that while many corporations align their fiscal years with calendar years, others do not:
Exxon Mobil and General Electric have December 31 as their fiscal year-end.
Microsoft has June 30, and Wal-Mart has January 31.