Prior to eating any food or drinking any liquid, we are commanded by our Sages to bless the Almighty who provides us with food and drink. Although it is man who plants and reaps, it is the Almighty's design that what we plant grows into fruit, vegetables and vegetation that is the basis of all life. The blessing varies the blessing for fruit grown on trees, ends with "who creates the fruit of the trees", while the blessing for vegetables grown on the ground, ends with "who creates the fruit of the ground". Food that is neither fruit nor vegetables, such as meat, fish, cheese, eggs etc., and liquids, apart from wine, have their own blessing, which ends "by whose word all things exist". Food made of any of the five species of grain such as for example cake or pasta, have their own special blessing “who creates all kinds of food”

However, bread is of such importance called "the staff of life” that it has its own blessing, and ends "who brings forth bread from the earth". Bread is considered such an essential part of all meals that the Sages have decreed that the blessing on bread includes all the food that we eat in that meal.

Wine which is an important part of our lives in that we sanctify the Sabbath and Festivals with wine and is an essential part of the wedding and circumcision services, of all liquids has its own blessing which does not mention wine, but ends "who has created the fruit of the vine". Incidentally, the blessing for grapes from which wine is made is the standard one for fruit of the tree.

The table on which we eat our meals is compared to the Altar in the Temple and we give thanks to the Almighty for providing the meal we eat on it. By eating bread with the meal, we make what we eat into a “proper meal” as it were, as distinct from a snack. In the Temple of old the Priest would wash his hands before eating the Terumah, (the gift of the grain given to the Priest) To stress the importance of this “proper meal”, and to commemorate the action of the priest we also wash our hands, prior to the blessing we make over the bread. Washing the hands prior to a “proper meal” converts the blessing over bread into a blessing over all the individual foods and types of food we eat in that “proper meal”

This washing of our hands before a meal is called in Hebrew, נטילת ידי (‘netilat yadayim’) and is done by pouring water from a vessel twice (some say 3 times) over each hand in turn making the special blessing which appears next in the Haggadah. Between this blessing and the two which we make next, one over the Matzah as bread and one which we make only on the Seder night on eating Matzah in accordance with the commandment to eat Matzah, there should not be any distraction such as talking or untoward or unnecessary gesturing.

haggadah Section: Rachtzah
Source: My Journey Through the Haggadah, Yekutiel Atkins