Entropy is a measure of disorder, the higher the entropy the greater the disorder. Uniform systems have less entropy than random systems.
Data is expressed in binary in computers, expressed as ones and zeros. Eight bits are a byte, data is stored in bytes, if a stream of data is less than a byte, it is padded by adding zeros before it. A unsigned byte can express numbers between 00000000 and 11111111, which is 0 to 255 in decimal and 00 to FF in hexadecimal.
A formatted "empty" disk has uniform bytes, uniform bytes have no information, by writing data to it, its randomness has increased and thus entropy is increased.
Now, I am wondering, 1, do freshly formatted disks, with all bytes the same (i.e. 00), have entropy of 0?
2, Lets say the disk with all bytes 00 is empty, when all bytes of it are used the disk is full. When does the disk have the maximum entropy? When it is half full? Or equal number of all possible 256 bytes randomly distributed?
By entropy I mean this: https://en.wikipedia.org/wiki/Entropy_(order_and_disorder)
By hard drive I specifically mean Hard Disk Device, which is the spinning electro-magnetic disk.
As far as I know, binary data is stored in such a device by changing the magnetic microstate of the platter, changing magnetic polarity of a small area by magnetization from the read/write head. This process requires energy. Though information itself is hard to be associated with energy, storing, retrieving and processing information all requires energy.
So the individual bytes of information do have energy, magnetic energy, which is a form of electro-magnetic energy, the energy is equal to energy difference of the hard disk caused by the process to store information. And they do have mass, no matter how small it is, by E=m*c^2.
And there are four elemental forces: electromagnetic, gravitation, strong nuclear and weak nuclear. Every force in the macrocosm that is not gravitation is EM, and thermodynamic energy is the average kinetic energy of the random motion of the constituent particles, particles are waves, and changes of EM cause changes of thermodynamic energy, so thermodynamic energy is a form of EM.
Thus the binary data is related to thermodynamic energy, QED.