Consensus mechanism is a fancy term to describe how a transaction is verified. Bitcoin uses proof of work, meaning computers basically need to solve complex math equations and melt the inside of your house in order to mine bitcoin.
Solana is a lot more environmentally friendly, as it uses a combination of proof of stake with a unique consensus model called ‘proof of history’.
Proof of history works by integrating time into the blockchain data. In short, each of the validators knows their order without having to communicate back and forth. It’s kind of like being assigned a specific job at a factory without having to see exactly which job has been done. This lessened communication requirement directly translates into a much faster network. Henry Ford would be proud…
We often take time for granted, but computers have to constantly ask themselves ‘What time is it?’ since they can’t look at their phone or look at the sun, they rely on nodes to do this before submitting a block.
One analogy we can use:
Suppose you were making a video about how to cook chocolate cake. There’s 5 steps to making chocolate cake, so you assign 5 video editors each with their own step. We want to read the steps in order once the editors submit them, but they are each working from different time zones so you’re not sure when each step will be sent. The clips might not all arrive at the same time(different delivery times) but you can organize the steps once you get them. By not asking each video editor to check whether the last steps have been done before theirs, it saves time.