First thanks for this very clear and simple explanation. I actually get it. One questions though on something that is not clear: You say at 2:07 in your video "then I need to try many variations of hashing, this process of trying all of these variations is called mining". I do not understand what you are varying to try a new variation. Are you changing the nonce, the text in the data box or something else when you mine? Thanks for your help.