Depending on who the cam grinder is, grind numbers indicate which combination of lobes and how they're placed in relation to each other. Each company has their own "lobe library", which they keep the "master" specs for a given lobe on file. When there's a grind ordered, they take out each "master" (a funny looking lobe thingy, one for intake, one for exhaust) and index them in the appropriate position, to get the desired "grind".
Each cam company uses a different numbering "scheme" to identify their own grinds. Therefore, grind numbers mean very little except to identify the cam and it's maker.
Jim