iTechGuides is reader-supported. When you buy through links on our site, we may earn an affiliate commission. As an Amazon Associate I earn from qualifying purchases. Learn more
A Web3 app, or dapp, is a normal-looking web interface that talks to a smart contract running on a decentralized network. Your frontend never runs the shared logic itself. It asks a blockchain node for data, asks a wallet for permission to act, and sends requests that the network processes. This guide uses Ethereum as the concrete example, because “Web3” is a broad label and the stack described here is Ethereum’s. Other chains and projects may split these jobs differently.
The short version, as a restaurant
Imagine a restaurant where the dining room is a website, but the kitchen rules and the order book are kept by a group of people who nobody controls alone. This is an analogy, not a literal description of every chain. It is useful because each part of a dapp has a clear job, and the jobs stay separate.
| Layer | Restaurant analogy | What it does in an Ethereum dapp |
|---|---|---|
| Frontend (HTML, CSS, JavaScript) | The menu and ordering screen | Shows data, collects user input, and prepares requests |
| Wallet / provider | The keyring and approval desk | Exposes an API the app can call, and asks the user to approve actions |
| JSON-RPC and node access | The messenger between the dining room and the kitchen | Carries read requests and broadcasts signed transactions to the network |
| Blockchain | The shared rulebook and record book | Stores the state that everyone agrees on |
| Smart contract | A rule-following machine in the kitchen | Runs the application logic exactly as deployed |
| IPFS (optional) | A shelf where the printed menu files are kept | Can store and serve frontend files; does not execute contracts |
How the frontend and the smart contract relate
Ethereum.org’s technical introduction to dapps defines the category this way: “A decentralized application (dapp) is an application built on a decentralized network that combines a smart contract and a frontend user interface.” The same page describes the smart contract as the dapp’s backend, “for lack of a better term,” while the frontend can be written with ordinary web technologies and can call that backend. From a browser developer’s point of view, the app looks like any other web or mobile app. The difference is where some of its logic and state live.
A smart contract is code deployed on-chain. Ethereum.org notes that once deployed, it runs as programmed and cannot be changed, so design and testing carry more weight than they do for a server you can patch at 2 a.m. Client libraries use the contract’s ABI (its published description of functions and their inputs) to build calls to it. Treat the contract as the application-logic layer, not as a replacement for every conventional backend service. Things like user profiles, email, or large media files are often still handled elsewhere.
#1 Best Overall
How data flows: the read path and the write path
A frontend needs a route to a blockchain node for two very different jobs. The Ethereum.org stack page describes the node connection as using the JSON-RPC API. The two paths below are the ones your code will actually take.
Read path: showing chain data
A read asks the network for information without changing anything. Typical examples are an account balance or the current result of a contract function. Reads do not require a transaction, and the user does not need to sign anything to see them.
- The frontend calls a function in a client library, which builds a JSON-RPC request.
- The request goes to a node the app is connected to.
- The node returns the data, and the frontend renders it like any API response.
Write path: sending a transaction
Ethereum.org’s stack page gives transferring ETH and calling a contract function as examples of broadcast transactions. A write is a request to change state, so it has an extra step that reads never need: the user’s wallet has to approve it.
- The user clicks an action, such as “Send” or “Mint,” in your interface.
- The frontend asks the wallet, through the provider API, to send a transaction with specific details.
- The wallet shows the request to the user. If the user rejects it, nothing is sent.
- If the user approves, the signed transaction is broadcast through the node path.
- The frontend waits for the network to process it, then refreshes the displayed data through the read path.
Practical consequence: a write is never instant from the user’s perspective. Build loading and pending states into your UI, because the change becomes visible only after the network processes it.
Rank #3
What the wallet does
The wallet, sometimes called a provider, is the boundary between your app and the user’s keys. The interface people usually see is a browser extension or a mobile wallet that the page can talk to.
The provider API
EIP-1193, the Ethereum Improvement Proposal that describes this convention, says wallet key-management software exposes a JavaScript API to a web application. The app asks for access through explicit methods, and the provider, wallet, or client handles each request. That explicit request model is the main design idea: the app can ask, but the wallet decides what the user sees and approves.
What the wallet does not do
The standard describes a provider API, not a way for a website to receive key material. Your frontend should never need a private key or seed phrase to work. If your design asks users to paste keys into a page, you have left the intended architecture.
Where the node fits
Your frontend reaches the network through a node, and the node speaks JSON-RPC. There are two broad ways to get one, and the choice affects control and operations more than the code you write.
Best Value
| Option | What you control | What you take on |
|---|---|---|
| Direct or self-hosted node | Full control over which node answers your requests | You run, update, and monitor the node yourself |
| Remote provider endpoint | Setup is quick, and you do not run infrastructure | You depend on the provider’s availability and terms |
The sources used for this guide describe the JSON-RPC interface and the stack, but they do not compare specific RPC providers or measure their performance, so this article does not rank them. Choose based on your own availability, cost, and trust requirements, and test the endpoint your users will actually hit.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Does IPFS replace the blockchain?
No. IPFS, the InterPlanetary File System, is a separate layer. The IPFS documentation describes data representation and peer-to-peer connectivity as parts of its system. Ethereum.org’s dapp page notes that a dapp’s frontend may be hosted on decentralized storage such as IPFS. That answers a question about where your HTML, CSS, and JavaScript files live. It does not answer a question about where your application logic runs.
The clearest way to see the split is to compare hosting choices for the frontend and then look at what each one still needs.
Free tools Windows power users keep installed
One-click scans. No signup required.
| Concern | Conventional web hosting | Decentralized storage (IPFS) |
|---|---|---|
| Serves the frontend files | Yes | Yes, when the files are published there |
| Executes smart contract logic | No | No |
| Connects the app to a blockchain node | Still required | Still required |
| Replaces the blockchain’s record of state | No | No |
In both columns, the app still reaches the chain through a wallet and a node. Hosting the files differently changes where they are served from, not how the app reads or writes on-chain state.
Where this model stops
- The architecture described here is Ethereum’s. “Web3” is broader, and this article does not compare other chains.
- Not every project labeled Web3 uses the same stack. Check which wallet, node, and contract conventions a given project uses before assuming they match.
- Deployed contracts cannot be changed, so bugs in contract code are harder to fix than bugs in a web frontend. Test contract behavior before you point real users at it.
- Frontend bugs still matter. A broken interface can send a wrong transaction request even when the contract is correct, so review every request your app builds.
Sources and dates
- Ethereum.org, “Technical introduction to dapps,” last updated July 13, 2026. Covers the dapp definition, the frontend and smart contract relationship, and possible IPFS hosting.
- Ethereum.org, “Introduction to the Ethereum stack,” last updated October 21, 2025. Covers JSON-RPC node access, read and broadcast examples, and JavaScript client libraries.
- Ethereum Improvement Proposals, EIP-1193. Defines the wallet provider JavaScript API and its explicit request model.
- IPFS Docs, the official documentation landing page for IPFS components and decentralized storage concepts.
The update dates are page-maintenance dates, not measures of how widely any of these tools are used.
Quick Recap
“
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
