The main sources are as follows:
1. Accounts of Foreign Travellers: Iban-batuta and Marco Polo travelled to India during the Sultanate period and wrote accounts about the personality of Sultans and knowledge about different sectors.
2. Royal Description: Tughlaq Nama, Tarikh-i-Alahi, Tarikh-i-Firozshahi, Futuhat-i-Firozshahi, Tarikh-i-Mubarakshahi, and Makhzari-i-Afghan, etc. were the royal descriptions, where we get knowledge about Delhi Sultans and main events.
3. Historical Monuments: The historical structures during the period of the Delhi Sultanate include Quwat-ul-Islam Mosque, Alahi Darwaja, Tughlakabad, Hauz Khas, Lodhi Tomb, Firozshah Kotla, etc. These buildings and monuments give us knowledge and information about the artistic hobbies of Delhi Sultans.