[ben_w]

First: powered tools, mechanised factories, basic but modern chemical processes.

Second: mass production, interchangeable parts, reliable steel, telegraph and other basic uses of electricity.

Third: computers and everything related to them.

Fourth: all the buzzwords and not much substantial at this time — though when the dust settles, I won't be surprised if at least a few currently popular things are still seen as relevant and not merely flash-in-the-pan cultural artefacts like the 18th Amendment, patent medicine, or Spiritualism.