HOW THE ADHAN (the call to prayer) STARTED

[Bilkis]

(v5:58) And when you proclaim the call to prayer (ADHAN) they take it (but) as a mockery and fun; that's because they are people who who understand not."(v5:58) and also the statement of Allah (SWT) "when the call for prayer is proclaimed on the day of Friday."(62:9) .
Narrated Anas the people mentioned the fire and the bell ( they suggested those as signals to indicate the starting of prayers) and by that they mentioned the Jews and the christians,then Bilal was ordered to pronounce adhan for the prayers by saying it's wordings twice (in double), and for the iqamah ( the call for the actual standing for the prayers in row) by saying it's wordings once (in singles) (iqamah is pronounced when the people are ready for prayers).( SAHIH AL-BUKHARI;VOL.1 HADITH NO.577).

THE WORDING OF ADHAN: Allahu-Akbar, Allahu-Akbar, Allahu-Akbar Allahu-Akbar; Ash-hadu an la ilah illallah ; Ash-hadu an la ilah illallah; Ash-hadu Anna Muhammad -ar Rasul-ullah ; Ash-hadu Anna Muhammad -ar Rasul-ullah; Hayya,-alas-salah, Hayya -alas-salah; Hayya alal-falah, Hayya alal-falah; Allahu-Akbar Allahu-Akbar;La ilaha illallah.