Ethereum is a permissionless, open-source smart-contract blockchain that serves as a programmable settlement layer for tokenized assets, stablecoins, and on-chain financial applications, with Ether (ETH) used to pay “gas” fees and to secure the network via staking. Launched on July 30, 2015, it has been upgraded to improve fee formation and scalability.
The London upgrade on August 5, 2021 (notably EIP-1559) introduced a base-fee mechanism and fee burning, increasing fee transparency and affecting ETH’s net issuance dynamics.
On September 15, 2022, The Merge completed the transition to Proof-of-Stake, replacing mining with validator-based security.
The Dencun upgrade activated on March 13, 2024 and added EIP-4844 (proto-danksharding), lowering data costs for Layer-2 rollups while keeping settlement on Ethereum mainnet.