Easter 2013 falls on March 31st this year - Ash Wednesday is on February 13th.
...but how do they figure out Easter each year...
Easter Day always falls on a Sunday and is the first Sunday after the Paschal Full Moon. This full moon is different than the astronomical full moon and usually takes place 1-3 days after that moon. Pope Gregory the 13th was the first to set up this calculation to determine Easter, working with astronomers and mathematicians. Easter Sunday always falls between the days of March 22-April 25. Easter Day falls on the following dates in the coming years:
Easter can only fall on one of 35 different dates. It takes over 5,000,000 years for the cycle of dates to repeat exactly. April 19 has had Easter on its date over 220,000 times, making it the most common day for the holiday. However, April 16 and March 31st are the most common days from 1853-2030, each repeating over 20 times (see graph below). It can take hundreds of years for a date to host two Easter Sundays, for example, March 23 was Easter in 2008 and won't see another Easter until 2160.
Easter Sunday caps off the end of Holy Week. The week starts with the previous Sunday, also known as Palm Sunday. The week contains Maundy Thursday, also known as Holy Thursday, Good Friday, and Holy Saturday or Silent Saturday. There are some countries that celebrate Easter on two days and celebrate Easter Monday on the following day.
There are many celebrations and rituals associated with Easter that don't rely on the religious aspects of the holidays. These are particularly associated with cultures in the Western world and those cultures that speak English. The idea of the Easter Bunny is one such concept. Adults leave Easter baskets filled with candy, toys and other small gifts for children and state that the Easter Bunny brought it. Often times some one dresses up in an Easter bunny costume and hosts the easter egg hunt.
Adults and children alike decorate Easter eggs throughout the week. It's a popular idea to hide the eggs around the house or yard for the children to find. There are other events associated with Easter such as attending church, eating ham for the main dinner and even eating certain types of candy like chocolate eggs or coins and marshmallow or chocolate rabbits.
Which Day is Easter Each Year?
What is Easter?
Easter is a Christian holiday that is celebrated every year. The Church believes that Jesus Christ was resurrected, and Easter is a celebration of his resurrection. The Friday before this holiday is known as Good Friday, in Christian based religions. The day is also the end of Lent, which is celebrated by the Catholic Church. It's unusual in terms of a holiday because its date changes each year.
For more information on Easter see:
Easter Discussion of the history of Easter
How is the Date of Easter Determined? Offers a concise answer to this question.