Innovation most often, it seems, comes in the form of combining existing elements. How things are combined, the “form and fit” of the blending (combining) has a large impact on the outcome, but conceptually all the items being combined already exist.
Combinations can be between items within the same “conceptual category” such as iPhone and Laptop combined to iPad . Combinations can be between two disparate conceptual-categories such as Pet and Rock, or Shower and Radio. The scope and boundaries of any “conceptual category” certainly makes for lively discussion, perhaps best with a latte and a cigar. I believe the argument could be made that the inventions of Leonardo da Vinci could be distilled to combinations of existing elements. The Archimedes screw was already in existence to pump water from the Nile river. The da Vinci helicopter, whether a device that descends slowly through the atmosphere (ie: the water turning the screw) or a device which ascends in the atmosphere (the screw moving through the water)
Certainly I mean no disrespect to one of the greatest inventors of his time. The point is not personal; it is that innovation comes most often from combining existing elements from similar or disparate conceptual categories.