Fat Tuesday.

Doughnut Day.Shrove Tuesday.Mardi Gras.Pancake Day.Carnival.Whatever you call Tuesday, it is the day before millions of Christians begin their Lenten journey of sacrifice and prayer in preparation for the celebration of Christ's crucifixion and resurrection.According to the AmericanCatholic.org, the history of Fat Tuesday dates back centuries, when Mardi Gras, which translates to Fat Tuesday, was celebrated by slaughtering and feasting upon a fattened calf on the last day of Carnival.The day is a day of celebration and indulgence, allowing people to eat all they want of rich foods typically doughnuts, pancakes and other pastries before giving up something on Ash Wednesday, the beginning of a 40-day fasting period for Christians.The custom is believed to be a way to use up fat, eggs and dairy before Lent begins.In preparation of the Lenten season, multiday celebrations take place across the world and end at midnight on Fat Tuesday.In Europe and Latin America, there is Carnival, which translates to "farewell to the flesh," and is a celebratory season that begins on the Epiphany on Jan. 6, and ends on Shrove Tuesday.In the United States, there is Mardi Gras.According to the Mardi Gras official website, the event came to America in 1703, when the first celebration took place in the tiny settlement of Fort Louis de la Mobile.Today, it is celebrated in New Orleans, and attracts millions of revelers to watch parades, eat fatty foods and over imbibe.