If you’re reading a website about cheese (this one) and you’ve never had parmigiano-reggiano (the topic at hand) then… well, it all depends on if you’ve had the “fake stuff” or not.
It’s unfortunate, though not at all surprising, that the colloquial term for parmigiano, parmesan, is used by its many imitators. If you’ve only had the latter then you will not be forgiven until you’ve bought the former. [Don’t worry, parmigiano-reggiano is a name protected by European law, much like roquefort or champagne, so you don’t have to be Inspector Montalbano to find the real deal.] But, if you’ve never tasted anything of the kind, then I applaud you for getting through life as you have.
There’s certainly a discernable difference between genuine and imitation parmesan. The non-authentic variety, when grated, is like yellow dust compared to the real thing, which is much more crumbly and pleasing to the touch. It’s somewhat like the difference between store-bought, pre-grated pepper and freshly grated pepper.
Speaking of which, I have to state that freshly grated parmesan and freshly grated black pepper is one of the all-time great food combinations. They go together better than PB&J, or even PJ&Duncan.
That being said, if you’ve only ever had parmigiano-reggiano in grated form then try some slices of it at the next opportunity. It may have a gritty texture but it’s far from unpleasant and the flavour hits you with more immediacy than most other cheeses. Plus, it’s much more crunchy than so called “crunchy cheddars.” Then, after that, go back and try a spoonful of grated parmigiano. The feeling is surprisingly smooth and it’s far better than a spoonful of gravy granules!
Finally, again for those that haven’t tried this, parmigiano-reggiano can lead to a great slice of cheese-on-toast. Note though that it doesn’t melt as easily as, say, cheddar and don’t be afraid of any white spots that look like mold. They’re just deposits of calcium lactate, the many crystals of which give this cheese its fantastic bite.