What is the significance of the darood?

Salawat Ibrahimiya Allahumma salli ala muhammadiw wa ala aali muhammadin kamaa sallaita ala ibrahima wa ala aali ibrahima innaka hamidum majid. allahumma baarik ala muhammadiw wa ala aali muhammadin kamaa baarakta ala ibrahima wa...