Matzah is made of specially supervised flour and water, which must be baked before the dough has had time to rise — within 18 minutes or less. It is the only product based on the five grains (wheat, barley, oat, spelt & rye) which Jews may eat during Passover, and it must be made specifically for Passover use, under rabbinical supervision.
Eating matza on Passover commemorates the unleavened bread eaten by the Jews when they left Egypt in such haste that there was no time for the dough to rise. Shmurah matza involves additional steps of supervision and is recommended for use at the Seder.
Not eating gebrokts (Yiddish, meaning matza that has become “wet”) is a custom by which some Ashkenazim will avoid putting matza (or any derivative, such as matza meal) into any liquid to prevent the possibility that improperly mixed dough, leaving stray flour that was never exposed to water (and therefore still susceptible to leavening) would subsequently become chametz when finally exposed to liquid.
The Seder is a symbolic reenactment of the Exodus, with a compelling message for young and old alike. The Seder details the journey of the exodus from Egypt by Jewish slaves following a traditional order of blessings, eating symbolic foods, narratives, commentaries and song.