Maundy Thursday April 22 inclusive, but these dates fall on different days depending on whether the Gregorian calendar or Julian calendar is used liturgically. Eastern churches generally use the Julian calendar and celebrate this feast throughout the 21st century between April 1 and May 5 in the more commonly used Gregorian calendar. The liturgy held on the evening of Maundy Thursday initiates the Easter Triduum, the period which commemorates the passion, death, and resurrection of Jesus; this period includes Good Friday and Holy Saturday, and ends on the evening of Easter. The Mass of the Lord's Supper or service of worship is
360-day calendar used a 360 day calendar. Romans initially used a calendar which had 360 days, with varying length of months. The Rig Veda describes a calendar with twelve months and 360 days. In the Mayan Long Count Calendar, the equivalent of the year, the tun, was 360 days. A duration is calculated as an integral number of days between start date A and end date B. The difference in years, months and days are usually calculated separately: There are several methods commonly available which differ in the way that they handle the cases where the months are not 30 days long,