Hi
These terms used to describe the level of details exposed by a component public interface.
A component which its public interface expose so much details about it internal structure and function called fine-grained.
A component with a lower level of details in its public interface called coarse-grained.
when we want to have afew method call and perform many operation we use
coarse-grained -usually in remote clients-
In OR mapping when you map each table to one
EJB -so each row is one EJB-
you did a fine-grained mapping (its not recommanded) and vice-versa.