Easter, Pascha, or Resurrection Day, is an important religious feast in the Christian liturgical year. It celebrates the resurrection of Jesus, which Christians believe occurred on the third day after his crucifixion some time in the period AD 27 to 33.

Easter also refers to the season of the church year called Eastertide or the Easter Season. Traditionally the Easter Season lasted for the forty days from Easter Day until Ascension Day but now officially lasts for the fifty days until Pentecost. The first week of the Easter Season is known as Easter Week or the Octave of Easter.

April Fools' Day or All Fools' Day, though not a holiday in its own right, is a notable day celebrated in many countries on April 1. The day is marked by the commission of hoaxes and other practical jokes of varying sophistication on friends, enemies and neighbors, or sending them on fools' errands, the aim of which is to embarrass the gullible. In some countries, April Fools' jokes (also called "April Fools") are only made before noon on 1 April

Earth Day is a name used by two different observances held annually in the (northern) spring, both intended to inspire awareness of and appreciation for the Earth's environment. Earth Day is in the public domain and open to all persons to shape. Some grassroots Earth Day organizers seek to move the date of the observance to the Summer Solstice, to take advantage of the warm temperatures in the Northern Hemisphere (where most people live) to create greater participation.