A star note is a Unite States bank note that has an asterisk (*), or star, before or after the serial number. The Bureau of Engraving and Printing inspects currency for printing errors prior to releasing notes into general circulation. When notes are discovered that have been printed incorrectly (such as having the serial numbers upside down, etc.) these misprinted notes (error notes) are replaced with star notes because no two bills can be produced with the same serial number. They are used to maintain a correct count of notes in a serial number run. By their nature, star notes are more scarce than notes with standard serial numbers and as such are widely collected by hobbyists. Some of the highest prices paid for modern (post-1928) U.S. banknotes have been for star notes. A star note is also substituted for the last note in a series rather than printing a note with a serial number consisting of eight zeros.