Five months ago, my first post in r/ethereum (well, at least with this alias) was about calling for [sunsetting the “Ethereum 2.0” moniker](https://www.reddit.com/r/ethereum/comments/mhoz7a/opinion_time_to_sunset_the_ethereum_20_branding/). I have since learned that Eth2, Eth 2.0 or Ethereum 2.0 branding is not going anywhere, and will continue to be used. However, it’s worth striving for accuracy and calling things by their correct nomenclatures.
Philosophically, you can continue to call “Eth2” as an umbrella term for upcoming Ethereum upgrades. Or, narrow it down to the Merge or data shards. But it’s best to just call them “The Merge” and “data shards”. We have equally significant upgrades recently done (EIP-1559), and incoming (statelessness & state expiry), which technically don’t fall under Eth2. You also have releases like Arbitrum One in a week’s time, which are technically outside of Ethereum, which is actually more impactful for the user experience than any other upgrade, and finally delivers the vision of a smart contract chain with relatively low fees without compromising highy security and decentralization. The answer to the oft-obsessed-over question “wen low gas” is not Eth2 – it’s rollups like Arbitrum One, and it’s happening in a week’s time! Though, yes, it’ll take time for rollups to mature, and data shards will reduce gas further, so it’s a couple of years long journey – but it begins in mere days, not weeks! So, it all gets complicated, and I just prefer to consider all of these “Ethereum upgrades”.
More technically, eth1 and eth2 (not called these anymore! Just for illustration purposes here) are two different chains. Eth1 is what everyone uses now, secured by proof-of-work mining. Eth2 is the beacon chain that went live in December 2020 – this is the proof-of-stake chain. What The Merge does is to, put it simply, merge eth1 and eth2 and turn off proof-of-work mining. At this point, it’ll be One Ethereum again.
So, what’s changing? You can read the details in [The Great Renaming document](https://notes.ethereum.org/@timbeiko/great-renaming).
What was previously called eth1 is now called the **execution layer**. The Merge will see this layer live on, and to the end user it’d be barely noticeable. All your ETH, tokens, DeFi positions – eveything will remain exactly the same. It’s important to note that the execution layer’s gas fees will remain high for the foreseeable future. But this won’t matter because all users that want low gas fees will be using rollups or rollup-like solutions. Data shards will lower fees on rollups further, but not necessarily on the execution layer.
What was previously called eth2 is now called the **consensus layer**. This is the proof-of-stake layer, which will drive the execution layer after The Merge. Data shards will be built on top of the **consensus layer**, so really, it’s more like the consensus and data availability layer in the future.
As we head into The Merge, we should try to stop using the ~~Eth2~~ moniker, and start thinking of all of these as One Ethereum again. We can discuss these various upgrades independently.
– Want to discuss how fees will be lowered? Talk about rollups.
– Want to discuss when proof-of-work is replaced with proof-of-stake? Talk about The Merge.
– What to discuss how fees on rollups can be lowered further? Talk about rollups + data shards.
– Want to discuss how the beacon chain works or how it’ll be upgraded? Talk about the consensus layer.
PS: Of course, consensus layer and execution layer can be quite a mouthful. So here are suggestions for abbreviations: ethx and ethc. Or, ethex and ethcon. Or, ex and con.