2015 (MMXV) will be a common year starting on Thursday. In the Gregorian calendar, it is the 2015th year in the Common Era (or Anno Domini), the 15th year of the 3rd millennium and 21st century, and the 6th of the 2010s decade.

In the terminology of Islam, duʿāʾ (Arabic: دعاء‎, plural: daʿawāt دعوات; also transliterated Doowa) literally meaning invocation, is an act of supplication. The term is derived from an Arabic word meaning to 'call out' or to 'summon', and Muslims regard this as a profound act of worship. This is when Muslim people from all over connect with God and ask him for forgiveness and favors. The Islamic prophet Muhammad is reported to have said "Dua is the very essence of worship," while one of God's commands expressed through the Qur'an is for them to call out to Him:

There is a special emphasis on du'a in Muslim spirituality and early Muslims took great care to record the supplications of Muhammad and transmit them to subsequent generations.^{[citation needed]} These traditions precipitated new genres of literature in which prophetic supplications were gathered together in single volumes that were memorized and taught. Collections such as Imam al-Nawawi's Kitab al-adhkar and Shams al-Din al-Jazari's al-Hisn al-Hasin exemplify this literary trend and gained significant currency among Muslim devotees keen to learn how Muhammad supplicated to God.