I have an assembly of different material parts. I wanted to know the moment of inertia about a particular axis. I got to a point where I get an output coordinate system and when I click 'Mass Properties' in the 'Evaluate' tab, I get a list of the moments of inertia. But, in that list, it says 'Moments of Inertia about the center of mass' which has units of kilograms-meter^2 and is denoted by 'L'. There is also a list of 'Moments of Inertia about the output coordinate system' which has units of kilogram - meters and is denoted by 'I'. What is the difference between the afore mentioned moments of inertia about different coordinate systems? And why is it denoted with a different letter?

Please reply to this asap. An urgent need!