$ETH Ethereum (ETH) is the second-largest cryptocurrency by market capitalization, with a current price of around $2,050.

*Key Features:*

1. *Smart Contracts*: Ethereum's decentralized platform enables the creation and execution of smart contracts.

2. *Decentralized Applications (dApps)*: Ethereum supports the development of dApps, which are built on top of the Ethereum blockchain.

3. *Gas*: Ethereum's native cryptocurrency, Ether (ETH), is used to pay for transaction fees, known as gas.

4. *Proof-of-Work (PoW)*: Ethereum currently uses a PoW consensus algorithm, but plans to transition to Proof-of-Stake (PoS) with the upcoming Ethereum 2.0 upgrade.

*Ethereum 2.0 Upgrade:*

1. *Improved Scalability*: Ethereum 2.0 aims to increase the network's scalability and transaction capacity.

2. *Enhanced Security*: The upgrade will introduce a new consensus algorithm, PoS, which is more energy-efficient and secure.

3. *Sustainability*: Ethereum 2.0 is designed to be more sustainable and environmentally friendly.