If you haven’t been exposed to the principles of blockchain, but have only heard reviews of the technology, you might be under the impression that blockchain is a kind of distributed computer that does distributed computing, respectively. Nodes around the world, they say, are piecing together something more.

This notion is fundamentally flawed. In reality, all the nodes serving the blockchain do exactly the same thing. Millions of computers:

• Checking the same transactions against the same rules. Doing identical work.
• Writing the same thing on the blockchain (if they are lucky enough to be able to write it).
• Stores all the history for all time, the same, one for all.

No parallelization, no synergy, no mutual aid. Only duplication, and immediately a million times. We will talk below about why this is necessary, but as you can see, there is no efficiency. It’s more like the opposite.