The public call to prayer is called Adhan.

Описание: The Call for prayer for Fajr, known as the Adhan, is recited in Arabic and includes phrases like "Allahu akbar" (Allah is the greatest) and "Hayya 'alas-Salah" (Come to prayer). For Fajr, the Adhan includes the special phrase "As-Salatu khairun min an-naum" twice after "Hayya 'alal-Falah," which means "Prayer is better than sleep".
Sunnis believe that the adhan was not written or said by the Islamic prophet, Muhammad, but rather by one of his companions. Abdullah ibn Zayd, a companion of Muhammad, reportedly had a vision in his dream, in which the adhan was revealed to him by God. He related this to his companions; later, this news reached Muhammad, who confirmed it. Because of his stunning voice, Muhammad chose a freed Habeshan slave by the name of Bilal ibn Rabah al-Habashi to make the call for prayers. Muhammad preferred the call over the use of bells, used by Christians, and horns, used by Jews.