What is the meaning of Aal? Who are the aal of Muhammad ? In Durood-e-Ibrahim which we read in every prayer, why do we send salutations to the aal of Muhammad , and ask Allah to send salutations and barakah to the aal of Muhammad similar to that of the aal of Ibrahim?

Also, are Aal and Ahl the same?

Aal means family. There are various opinions among the scholars regarding who exactly are considered from the family of the Prophet Mohammad [1] (ﷺ).

As for why we send salutations to them, is because Allah taught His Prophet to teach his ummah this; thus it is an act of worship which we do out of pure obedience.

Aal and Ahl mean the same thing; however aal is more general than ahl. So ahl al-bayt is the family of the Prophet (ﷺ) which includes his wives. As for aal Muhammad, it includes his family, relatives and followers as well.

And Allah knows best.

[1] See: http://islamqa.info/en/10055