The Christmas tree is a decorated tree, usually an evergreen conifer such as spruce, pine, or fir or an artificial tree of similar appearance, associated with the celebration of Christmas. The modern Christmas tree was developed in early modern Germany (where it is today called Weihnachtsbaum or Christbaum), in which devout Christians brought decorated trees into their homes. The tree was traditionally decorated with "roses made of colored paper, apples, wafers, tinsel, and sweetmeats", with the apples and round ornaments representing the fruit of knowledge of good and evil from the Book of Genesis in the Christian Bible. In the 18th century, it began to be illuminated by candles which were ultimately replaced by Christmas lights after the advent of electrification.

Today, there is a wide variety of traditional ornaments,such as garlands, baubles, tinsel, and candy canes. An angel or star might be placed at the top of the tree to represent the archangel Gabriel or the Star of Bethlehem from the Nativity. Edible items such as ginger bread, chocolate and other sweets are also popular, and are tied to or hung from the tree's branches with ribbons. Christmas trees are variously erected on days such as the first day of Advent or even as late as Christmas Eve depending on the country.

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