All India quota or AIQ.
Every government medical college in India has limited number of seats.
Students get admission by qualifying the entrance exam and admission is through Merit.
Admission can be taken through All india quota or state quota.
Number of seats are divided into
1. 15% seats and
2. 85% seats.
By all india quota admission can only be taken in 15% seats, rest all 85% Seats are filled through state quota.
Suppose a college has 100 intake capacity. Then,15 admissions will be through all india quota and rest 85 admissions through state quota.
By all india quota, you can change your state also. You don't need to be a domicile of the particular state. For 85% quota, you have to be the domicile of the particular state to take admission.