Islamic Finance refers to the provision of financial services in accordance with Sharia norms, principles and rules. Sharia does not permit receipt and payment of "riba" (interest), "gharar" (excessive uncertainty), "maysir" (gambling), short sales or financing activities that it considers harmful to society. Instead, the parties must share the risks and rewards of a business transaction and the transaction should have a real economic purpose without undue speculation, and not involve any exploitation of either party.

To know more about Sharia norms find below some links may help you internalize the Principles of Shariah norms:
 
https://en.wikipedia.org/wiki/Islamic_economics
http://www.islamicinsights.com/religion/an-introduction-to-islam-and-economics.html
http://www.imf.org/external/themes/islamicfinance/
https://blogs.imf.org/tag/islamic-finance/
https://blogs.imf.org/2017/02/21/islamic-banking-proposals-get-imf-approval/