It is narrated from Hazrat Aisha (may Allah be pleased with her) that in Makkah Mukarramah, the initial obligation of prayer was in the form of two rak‘ahs each. But when the Prophet (peace and blessings be upon him) reached Madinah Munawwarah, by the command of Allah, two rak‘ahs were added to each prayer, except for Maghrib prayer, as it is the witr of the day, and Fajr prayer, as its recitation is lengthy. However, when the Prophet (peace and blessings be upon him) would travel, he would perform only two rak‘ahs for each prayer, according to the initial method.