Birkat hamazon, the blessing after the meal, is also known colloquially as "benching," the English version of the Yiddish term bentshn, which means to bless.
This blessing (which is actually a series of blessings) is mandated for use following any meal in which bread has been eaten, since according to Jewish law, eating bread officially constitutes a meal. Birkat Hamazon can be said sitting at the same table or in view of the same table where the meal was eaten. At weddings or Shabbat meals, it is often said communally.
Reciting the blessing after the meal is a mitzvah written in the Torah. Deuteronomy 8:10 states, "And you shall eat and be satisfied, and bless Adonai your God for the good land which God has given you."