Breaking the middle matzah | yachatz | יַחַץ

There are three pieces of matzah stacked on the table. We now break the middle matzah into two pieces. The host should wrap up the larger of the pieces and, at some point between now and the end of dinner, hide it. This piece is called the afikomen. After dinner, the guests must hunt for the afikomen in order to wrap up the meal.

We eat matzah in memory of the quick flight of our ancestors from Egypt. As slaves, they faced many false starts before finally securing their freedom. So when the word of their freedom came, they took whatever dough they had and ran with it before it had the chance to rise, letting it bake in the sun, and thus looking something like matzah.