In most languages of Christian societies, other than English, German and some Slavic languages, the holiday's name is derived from Pesach, the Hebrew name of Passover, a Jewish holiday to which the Christian Easter is intimately linked.
Together with Sukkot and Shavuot, Passover is one of the three pilgrim festivals (Shalosh Regalim) during which the entire Jewish populace made a pilgrimage to Jerusalem in the days of the Holy Temple.
In Israel, Passover is a 7-day holiday, with the first and last days celebrated as a full festival (involving abstention from work, special prayer services and holiday meals). Outside Israel, the holiday is celebrated for 8 days, with the first two days and last two days celebrated as full festivals. The intervening days are known as Chol HaMoed (festival weekdays).