• Entry
  • Reader's guide
  • Entries A-Z
  • Subject index

The calendrical convention of the leap year is important to how we keep track of time. In the Gregorian calendar, adopted in 1582, a leap year is a year to which an extra day (February 29) is added. This extra day ...

Loading
  • Loading...
locked icon

Sign in to access this content

Get a 30 day FREE TRIAL

  • Watch videos from a variety of sources bringing classroom topics to life
  • Read modern, diverse business cases
  • Explore hundreds of books and reference titles