What Is Ethereum? A Practical Overview of the Smart Contract Platform

Ethereum is a decentralized, global computing platform that executes and records the state of self-executing computer programs. Unlike networks designed primarily as digital currencies, Ethereum allows developers to build complex applications that operate exactly as programmed without central intermediaries ¹. At the core of this network is its native cryptocurrency, $ETH, which serves as the fuel to pay for the computational power required to run these applications ¹.

The Two Types of Accounts

To understand how Ethereum operates, one must first understand how it tracks ownership and execution. The Ethereum ledger does not use the Unspent Transaction Output (UTXO) model found in the Bitcoin network ². Instead, it uses an account-based model, which functions similarly to a traditional bank ledger where balances are tracked directly against specific addresses ¹.

Ethereum features two distinct types of accounts: Externally Owned Accounts (EOAs) and Contract Accounts ¹.

EOAs are controlled by private keys held by human users ¹. An EOA has an ETH balance, can send transactions to other accounts, and is required to initiate any action on the network ¹. Contract Accounts, commonly referred to as smart contracts, are controlled by code deployed directly to the blockchain ¹. While they also have an ETH balance and a unique address, they do not have a private key. Instead, they execute their pre-programmed logic only when triggered by a transaction sent from an EOA or another contract ¹. This architecture allows for the creation of decentralized applications (dApps) that can hold, transfer, and manipulate digital assets based on strict, immutable rules.

The Ethereum Virtual Machine (EVM)

If the account ledger is the database, the Ethereum Virtual Machine (EVM) is the engine that updates it. The EVM is a single, sandboxed runtime environment that executes smart contract code across the entire global network of Ethereum nodes ³.

Every node in the network runs an instance of the EVM to verify and execute transactions ³. This distributed design ensures high availability and censorship resistance, as no single entity can shut down or alter the execution of a smart contract. The EVM reads instructions written in bytecode, which is compiled from high-level programming languages like Solidity or Vyper ³. Because every node must execute every transaction to maintain consensus on the state of the ledger, computational efficiency is paramount. This requirement introduces the necessity of a pricing mechanism for computation.

Gas and Transaction Fees

To prevent spam, infinite loops, and resource abuse, Ethereum charges a fee for every computational step executed on the network. This fee is measured in gas, a unit that quantifies the computational effort required to perform a specific operation ⁴. Simple operations, like transferring ETH from one EOA to another, have a fixed gas cost of 21,000 units ⁴. More complex operations, such as interacting with a decentralized exchange, require significantly more gas because they involve reading and writing data to the blockchain's state.

The price of gas is denominated in gwei, where one gwei is equal to one-billionth of an ETH (0.000000001 ETH) ⁴. Under the current transaction fee mechanism, known as EIP-1559, the total transaction fee is split into a base fee and a priority fee (or tip) ⁴. The base fee is determined algorithmically by the network based on block space demand and is burned (permanently removed from circulation) ⁴. The priority fee is paid directly to validators to incentivize them to include the transaction in the next block ⁴.

To illustrate this with a worked example, assume a user wants to execute a standard ETH transfer (which costs 21,000 gas units). If the current market base fee is 20 gwei and the user adds a priority fee of 2 gwei, the total gas price is 22 gwei per unit.

$$\text{Total Fee} = \text{Gas Limit} \times (\text{Base Fee} + \text{Priority Fee})$$ $$\text{Total Fee} = 21,000 \times (20 + 2) \text{ gwei} = 462,000 \text{ gwei}$$

Converting this to ETH:

$$462,000 \times 10^{-9} \text{ ETH} = 0.000462 \text{ ETH}$$

If the market price of ETH is assumed to be $3,000, this transaction would cost approximately $1.39. If network congestion increases, the base fee rises dynamically, making transactions more expensive ⁴.

Proof-of-Stake and ETH Issuance

Ethereum transitioned from a Proof-of-Work consensus mechanism to Proof-of-Stake (PoS) during an upgrade known as "The Merge" ⁵. Under PoS, the network is secured by validators rather than energy-intensive miners ⁵.

To become a validator, an entity must deposit, or stake, 32 ETH into the official deposit contract ⁶. Validators are randomly selected to propose new blocks and attest to the validity of blocks proposed by others ⁶. In exchange for this service, they receive newly minted ETH as a reward ⁶. Conversely, if a validator acts maliciously or fails to maintain uptime, they can lose a portion of their staked ETH through a penalty process known as slashing ⁶.

This transition fundamentally altered the issuance dynamics of ETH. Under Proof-of-Work, the network issued substantial amounts of new ETH to reward miners. Under Proof-of-Stake, issuance dropped by approximately 90% ⁵. Because EIP-1559 burns the base fee of every transaction, high network activity can cause the amount of ETH burned to exceed the amount of ETH minted to validators [4, 5]. This dynamic can render ETH a deflationary asset during periods of high demand, though it remains inflationary during periods of low network activity.

The Scaling Roadmap

As adoption grew, the main Ethereum blockchain (Layer 1) faced scalability limits, resulting in high transaction fees during peak periods ⁴. To address this, the Ethereum community adopted a rollup-centric roadmap ⁷.

This strategy offloads transaction execution to secondary networks known as Layer 2 (L2) rollups ⁷. Rollups process hundreds of transactions off-chain, bundle them into a single batch, and post the compressed transaction data back to the Ethereum Layer 1 blockchain for final settlement and security ⁷. This approach drastically reduces transaction costs for users while inheriting the security guarantees of the main Ethereum network.

To support this roadmap, the network introduced "blobs" via EIP-4844 ⁸. Blobs are temporary data spaces attached to blocks specifically designed to carry L2 transaction data ⁸. Because this data does not need to be stored on the Ethereum ledger permanently, it significantly reduces the cost for L2 networks to post data to Layer 1, thereby lowering transaction fees for end-users on L2 networks ⁸.

Common Misconceptions

• "Ethereum and Ether are the same thing." Ethereum refers to the blockchain network and its global computing infrastructure ¹. Ether ($ETH) is the native cryptocurrency of that network, used to pay for computational fees and secure the consensus mechanism [1, 4].
• "Staking guarantees a fixed return without risk." Staking rewards fluctuate based on the total amount of ETH staked globally and the volume of network transactions ⁶. Furthermore, staking carries smart contract risk, hardware uptime requirements, and the risk of slashing for protocol violations ⁶.
• "Layer 2 networks compete with Ethereum." Layer 2 networks are complementary scaling solutions ⁷. They rely on Ethereum Layer 1 for settlement, security, and data availability, driving value back to the main network through transaction fees paid to settle L2 data [7, 8].

How Ethereum Connects to the Market

For market participants, Ethereum represents the foundational infrastructure for decentralized finance (DeFi), tokenized real-world assets (RWAs), and non-fungible tokens (NFTs). The value proposition of ETH is tied directly to the utility of the network. As demand for decentralized applications grows, transaction volume increases, leading to higher gas consumption, more burned ETH, and increased rewards for validators [4, 6].

However, Ethereum faces ongoing competition from alternative Layer 1 blockchains that prioritize high throughput on a single layer. The success of Ethereum's market position depends heavily on the seamless integration of its Layer 2 ecosystem and its ability to maintain security and decentralization while lowering barriers to entry for global users.