After eating the karpas, the leader of the Passover Seder takes the middle piece of matzah from the three matzot and breaks it in two. The larger fragment is called the Afikomen. This piece is either set apart or hidden by the leader. After the Passover meal it is eaten by all the participants as the last item of food on Passover evening.
The word afikomen is of Greek origin. However, because of its ambiguous etymology there is confusion over whether it denotes after-meal entertainment and songs, or dessert. The more popular interpretation has been the latter. This is in part due to the fact that the Afikomen is eaten after the meal like a dessert would be, and in part because the Afikomen represents the Paschal lamb.
The Mishnah instructs that the Paschal lamb must be the last food eaten the night of the Seder. However, since the destruction of the Temple in 70 c.e., the Afikomen has come to be a symbolic reminder of the Paschal lamb. In fact, some Sephardi celebrants still say while partaking of the Afikomen, “In memory of the Paschal meal that was eaten when satiated.” Because the Afikomen has come to represent the Paschal lamb, the Mishnah states “one may not add afikomen after the Paschal meal.”
As indicated above, it is traditional for the Afikomen to be hidden or stolen so that it may later be redeemed or ransomed for a reward. In the case of stealing, an advantageous time would be during the second washing of hands, just before the Passover meal. Particularly among non-Sephardi Jews, it is customary for either the leader or the children to hide the Afikomen so that one of the children might find it later and redeem it for a ransom. This custom is generally thought to be a tool for keeping the children awake and attentive. However, some Jews suggest there is a deeper purpose, namely to show the mysterious order of the universe, waiting to be uncovered. According to this perspective, the children seek to find the Afikomen because they represent all of us as children in the search for the unknown.
When the Afikomen is redeemed, it is often pieced together again with its complimentary fragment to show that “what is broken off is not really lost, so long as we remember and search after it.” To redeem the Afikomen, the leader and the child must barter with one another until an agreement is reached on what the Afikomen is worth. However, this could be predetermined by parents who wish to limit what their children can get from them.
Once the Afikomen is redeemed, it is immediately broken into pieces and eaten by every celebrant. It is to be eaten while reclining on the left side, promptly without interruption, and according to halachic sayings, before midnight.
It has become a folk tradition to preserve a piece of the Afikomen for protection against harm or the “evil eye,” or as a promise of longevity. The assumption behind this custom is that the Afikomen’s prominence in the Seder endows it with a special power. Therefore, even today, Jews in Iran, Afghanistan, Salonika, Kurdistan, and Bukhara keep a piece of the Afikomen in their pocket or home throughout the year. Some pregnant women hold a preserved piece of the Afikomen in their hand during delivery. It is believed that if preserved for seven years, a piece of the Afikomen can stop a flood if thrown into the midst of the turbulent river, or when combined with certain biblical verses, it can quiet the sea. Many Kurdi Jews and some Sephardi Jews in Hebron tie a piece of the Afikomen to the arm of one of their sons during the Seder and bless them, “May you so tie the ketubbah to the arm of your bride.” In Baghdad, someone would take the Afikomen and leave the Seder, then return disguised as a traveler. The leader would ask him, “Where are you from?” to which he would reply, “Egypt,” and “Where are you going?” to which he would answer, “Jerusalem.” In Djerba, the leader used to tie the Afikomen on the shoulder of one of the family, who would visit relatives and neighbors to forecast the coming of the Messiah. While all of these customs are interesting and could be explored further for deeper meaning and significance, it is important to recognize that these practices are grounded in folklore and not Jewish law. They are not essential parts of the Seder, but can add intrigue and meaning to the evening.
Kaplan, Mordecai M. The New Haggadah (New York: Behrman House,
Talmud. Pesachim 119b-120a
Klein, Mordell. Passover (Philadelphia: Jewish Publications Society
of America, 1973) 27
Mishnah. Pesachim 10:8
Drucker, Malka. Passover: A Season of Freedom (New York: Holiday
House, 1981) 51
Levin, Meyer. An Israel Haggadah for Passover (New York: Harry
N. Abrams, Inc., no date) 40
Davis, Rabbi Avrohom. The Metsudah Linear Passover Haggadah (Hoboken:
KTAV Publishing House, 1993) 10, 50
 All customs in this paragraph were taken from the Encyclopedia Judaica