> For the complete documentation index, see [llms.txt](https://docs.nexex.info/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.nexex.info/concepts/ethereum-erc20-and-dex.md). # Ethereum, ERC20 and DEX ## Ethereum > **Ethereum** is an [open-source](https://en.wikipedia.org/wiki/Open-source_software), [public](https://en.wikipedia.org/wiki/Types_of_blockchain), [blockchain](https://en.wikipedia.org/wiki/Blockchain_\(database\))-based [distributed computing](https://en.wikipedia.org/wiki/Distributed_computing) platform and [operating system](https://en.wikipedia.org/wiki/Operating_system) featuring [smart contract](https://en.wikipedia.org/wiki/Smart_contract) -- Wikipedia.com Welcome to the exciting world of building applications on the [Ethereum Blockchain](https://www.ethereum.org/). With Ethereum you can deploy applications or "Smart Contracts" that perform operations and persist state using a decentralized network of computers. Ethereum is often described as a platform for programming digital money. A transaction executes and is confirmed and verified by hundreds of different machines (nodes) distributed around the world. If you want to understand the how blockchains fundamentally work checkout [this visual explanation](https://anders.com/blockchain/). If you'd like to read more about Ethereum specifically, visit this [beginners guide to Ethereum](https://blog.coinbase.com/a-beginners-guide-to-ethereum-46dd486ceecf).Now that you have a basic understanding of what Ethereum is and does, let's talk about tokens. Fungible tokens (commonly referred to as [ERC20](https://github.com/ethereum/EIPs/issues/20)) are simple smart contracts that track the transfer of a unit of account. You can request this smart contract to [transfer](https://github.com/OpenZeppelin/zeppelin-solidity/blob/master/contracts/token/ERC20/BasicToken.sol#L31) tokens from your account to anyone else's. Others may also transfer tokens from their account to you. All of these requests are transactions on the Ethereum blockchain and cost a small transaction fee. For more information check out the [beginner's guide to Ethereum Tokens](https://blog.coinbase.com/a-beginners-guide-to-ethereum-tokens-fbd5611fe30b). ## DEX (decentralized exchange) A DEX is a decentralized exchange and is essentially a new type of pair matching that allows people to place orders and trade cryptocurrencies without an intermediary institution managing the ledger or controlling user funds. [What is a Dex](https://coincentral.com/dex-decentralized-exchanges-explained). --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://docs.nexex.info/concepts/ethereum-erc20-and-dex.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.