It is one week before Easter Sunday, and Catholics all over the world are celebrating Palm Sunday. So, what is Palm Sunday, and what does it signify in the Catholic Church?

According to About.com, Palm Sunday celebrates the arrival of Christ into the city of Jerusalem. It happened, according to the tenets of the faith, one week before his resurrection, and five days before his execution. Palm Sunday is sometimes referred to as Passion Sunday, and kicks off "Holy Week" in the church.

The biblical account of Palm Sunday can be found in Matthew 21:1-11; Mark 11:1-11; Luke 19:28-44; and John 12:12-19. The symbolism is captured in Zechariah 9:9 "The Coming of Zion's King -- See, your king comes to you, righteous and victorious, lowly and riding on a donkey, on a colt, the foal of a donkey." It was perceived that Jesus was declaring he was the King of Israel to the anger of the Sanhedrin (an act which, ultimately, called for his execution by crucifixion).

Palm Sunday gets its name from the belief that the Jerusalem crowd greeted Christ by laying palm fronds at his feet as he entered on a donkey.

Correction: An earlier version of this article contained improperly sourced material.