Ethereum is a decentralized and open-source blockchain with smart contract functionality. Smart contracts are applications that run as programmed without any possibility of censorship, fraud, or third-party interference. Ether (ETH) is the native cryptocurrency of the platform, also it has its own programming language, called Solidity. Ethereum is the most actively used blockchain, as it can be used in many areas with smart contracts. Ethereum allows deploying a lot of decentralized applications onto it, with which users can interact. Ethereum has already started implementing a series of upgrades called Ethereum 2.0, which includes a transition to proof of stake (PoS) and aims to increase transactions and make lower transaction fees. There are currently 8835 nodes on the Ethereum network.