Three matzot serve as a reminder of the three measures of the best flour, from which Abraham ordered Sarah to bake bread for the three angels who visited him. According to tradition, this happened on Passover.
Breaking matzo should be done in order to pronounce the words “this is the bread of poverty” (matzo in the Talmud is called the bread of poverty): just as the poor break bread to put aside a piece of it, so we break the “bread of poverty” (see step 5)
If there are 3 matzot on the table, you need to take the middle one and break it into two unequal parts (if there are 2 matzot, then you need to take the bottom one). It is the middle matzo that we break – this is reminiscent of the parting of the Red Sea that took place at night.
The larger part is set aside (hidden) as an afikoman until the end of the meal (see step 12), and the smaller part is returned to its original place between the upper and lower matzot.