A family floater policy covers all family members (Insured, his/her spouse and children) under one single policy. The Sum Insured floats over the entire Family and a consolidated premium needs to be paid. There is a limit on the no. of children that can be included and age before and beyond which they are not covered which varies from policy to policy. Parents of the insured are typically not included in a family floater policy.
An individual policy, on the other hand, provides health insurance coverage to only the individual for whom the insurance has been purchased.
While a family floater may turn out to be cheaper than taking 2 or more individual policies, the associated cover provided is at a family level. For e.g. if you take 2 Individual policies with a Rs. 200,000 Sum Assured each for yourself and your spouse, then both of you are covered for Rs. 200,000 each. However, if you take a family floater with a Rs. 200,000 Sum Assured then this limit applies to the two of you together.