Ashrafs, Ajlafs and Arzals

In theory Islam does not recognize castes.

 But practice among Indian Muslims is very different from theory

http://www.countercurrents.org/sikand150204.htm
http://www.booksandideas.net/Muslim-Castes-in-India.html

Some of the backward or lower-caste Muslim castes include Kunjra, Dhobi, Halalkhor, and Kalal (so called ranki involved in the profession of wine selling and making.)

https://en.wikipedia.org/wiki/List_of_Muslim_Other_Backward_Classes_communities

 The upper caste Muslim castes include  Pathan, Muslim Rajput, Turk, Sheikh, Khan, Syed, Rizvi, biradri, and Malik.
Ansari, Qureshi, etc are intermediate castes among Muslims,. like Hindu OBCs
 Genetic data has also supported this stratification.

The report commissioned by the government of India and released in 2006, documents the continued stratification in Muslim society.
While in the mosque all Muslims pray together,  but when it comes to marriage their attitude is very different, and most ashrafs ( upper caste Muslims ) will not marry Muslims of the lower castes.
 

I have many Muslim friends who tell me with pride that they are Rajputs.