Birkat haMazon (Blessing of the Meal) is known in English as the Grace/Blessing after a Meal.
A "Meal" is defined as a meal which began with the breaking of bread. Without bread, the meal is seen as just a "snack", and the formula for this Grace is not said.
The traditional Grace consists of 4 Talmudic blessings followed by a collection of later medieval petitions/requests (and the number and contents differ between the various Ashkenazi, Sefardi and Mizrachi forms of the Birkat haMazon).
The Four Talmudic blessings are
There are also additions for special occasions (the sabbath, festivals etc. - and for such matters as circumcisions, weddings and funerals).