When Jewish babies are born, in addition to their forename, they are given a Hebrew name. This name is the name by which Jews are called when called to the reading of the Torah in synagogue. It is also the name on their marriage contract, on their divorce document if they divorce, and on their tombstone.
A baby girl is named publicly in the synagogue, usually on the first Shabbat after she is born.
A baby boy is named at his circumcision. According to the Bible, all Jewish boys should be circumcised on the eighth day after birth.