Darood Sharif is the Urdu name for Salawat, which refers to invocations said to praise the Prophet peace be upon him. The words used in it are from hadith narrations in which the Prophet peace be upon him tells his companions how to say it, such as this hadith in Sahih al-Bukhari’s Book of Invocations:

Ka`b bin ‘Ujra met me and said, “Shall I give you a present? Once the Prophet (ﷺ) came to us and we said, ‘O Allah’s Messenger (ﷺ) ! We know how to greet you; but how to send ‘Salat’ upon you? He said, ‘Say: Allahumma Salli ala Muhammadin wa ‘ala `Ali Muhammadin, kama sal-laita ‘ala all Ibrahima innaka Hamidun Majid. Allahumma barik ‘ala Muhammadin wa ‘ala all Muhammadin, kama barakta ‘ala all Ibrahima, innaka Hamidun Majid.”