Here is the scenario. I will format my laptop and will backup my files in it. I cut my files and paste it on my Seagate HDD. When I finished formating my laptop, I cut and paste back again the same files back to my laptop. I noticed there is a changed in size on my Seagate HDD.
USED SPACE
Before: 1,101,750,411,264
After: 1,101,750,415,360
There is 4,096 bytes difference.
What do you think it is? Please check these pictures.
Before:
https://imgur.com/a/c6nnEHJ
After:
https://imgur.com/a/0UUkFZ0