The stored data is NOT 1's and 0's. You must have the proper circuits to analyse the voltage patters and extract the data from the disk.
Which is all under the hood crap nobody cares about and isn't taught until you take classes that focus under the hood. See that's the difference between what high school does and college. In college if they decide something is too complicated for this level they put it in a black box and tell you not to worry about, they tell you how to figure out the out put and if you really want to know what goes on inside the box take this other class. In high school if they decide something is too complicated for this level they make up a simple version that'll give the same output but isn't what's really going on. The college method is better because it doesn't give the student something to unlearn if they progress in that field. The high school method is stupid because it wastes time BSing the student, then if htey progress in that field more time gets wasted to unlearn the BS.