In Western Christianity, Easter marks the end of Lent, a period of fasting and penitence in preparation for Easter, which begins on Ash Wednesday and lasts forty days (not counting Sundays).
The week before Easter, known as Holy Week, is very special in the Christian tradition. The Sunday before Easter is Palm Sunday and the last three days before Easter are Maundy Thursday or Holy Thursday, Good Friday and Holy Saturday (sometimes referred to as Silent Saturday). Palm Sunday, Maundy Thursday and Good Friday respectively commemorate Jesus' entry in Jerusalem, the Last Supper and the Crucifixion. Holy Thursday, Good Friday, and Holy Saturday are sometimes referred to as the Easter Triduum (Latin for "Three Days"). In some countries, Easter lasts two days, with the second called "Easter Monday". The week beginning with Easter Sunday is called Easter Week or the Octave of Easter, and each day is prefaced with "Easter", e.g. Easter Monday, Easter Tuesday, etc. Easter Saturday is therefore the Saturday after Easter Sunday. The day before Easter is properly called Holy Saturday. Many churches begin celebrating Easter late in the evening of Holy Saturday at a service called the Easter Vigil.
Eastertide, or Paschaltide, the season of Easter, begins on Easter Sunday and lasts until the day of Pentecost, seven weeks later.