rate confusion

Nil RatedIt is the supply of goods and services that have 0% GST. Example: Grains, salt, jaggery etc. 

ExemptedIt is the supply of goods and services that does not attract GST and allows no claim on ITC. 
Example: Bread, fresh fruits, fresh milk and curd etc.

Zero RatedZero Rated Supplies include: 
- supplies made to any country other than India; and 
- supplies made to customers located in Special Economic Zones (SEZ) or SEZ Developers.

Non-GSTIt is the supply of goods and services that does not come under the purview of GST while other taxes maybe applicable. 
Example: Petrol, alcohol etc.

There is much confusion between nil rates and exempted among the businesses.. Nil rated supplies also needs reversal of ITC or not.? Under sec 42.?

Salt, jaggery(nil) and fruits, milk, curd(exempted) all are mentioned in schedule 1 of gst rate... How to differentiate.? Can you provide a link which differentiate them

you can use android app (GST Rate Finder) launched by CBEC .