-Field Outputs refer to quantities distributed spatially over the whole model(e.g. stress field, strain field, displacement field , temperature field etc.).
-History Outputs refers to quantities at specific points or quantities which characterize the whole model or a region of the model (e.g. elastic strain energy, energy dissipated plastically or other such quantities).
-Both outputs may vary with time (or with load variation over a sequence of steps).
If you're using CAE I think you'll have to create a point rigid part , and then from "Propety" section you can define a section (for your rigid point) containing mass and inertial behavior.
If you describe your model directly in the input file then
...I guess this might be of interest for you:
-ABAQUS Analysis User's Manual
-16.1.1 Point mass elements