As we know that when we call the Member Function from the Class then the Compiler will jump to that Function and after Executing all the Statements the Compiler will execute the Remaining Statements.
And Many Times there is a Situation when we Wants to Call a Function again and Again. So that Compiler will also jump to that Function Again and Again So that this will Decrease the Speed of Execution so that for Removing this Jumping. We uses the Inline Member Functions. The Member Functions those are declared by using the Inline are copied into the Memory of the Compiler.
So that when we first Time Call the Member Function of the Class all the Statements are gets copied into the Memory of the Compiler. So that When Compiler will execute that Method then this will never jump to that Method Again and again instead this will execute that Member Function from his Memory.