> For the complete documentation index, see [llms.txt](https://etherfi.gitbook.io/etherfi/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://etherfi.gitbook.io/etherfi/resources/ether.fi-whitepaper/technical-documentation.md).

# How ether.fi Works

How the ether.fi app, smart contract accounts, and the protocols behind each product fit together.

ether.fi is not one contract or one service. It is an app, a set of smart contracts, and a number of third-party protocols and providers. This page shows how they fit together.

## The app

The web and mobile apps show your account and let you build and approve actions. The app is not a custodian and not a blockchain. Transactions run onchain, in the relevant smart contracts, after you approve them.

## Wallets and smart contract accounts

You interact through a wallet or an ether.fi smart contract account. A smart contract account has owners, signing thresholds, admins, modules, and recovery settings. Together these decide which actions are allowed.

Holding a signing key does not mean every action needs a fresh signature. A module you enabled can act within the permissions its code and the protocol give it. The [Cash Vault](/etherfi/products/cash/vault.md) page explains this model in detail.

## The protocols behind each product

| Product     | What runs it                                                                                                                | Documentation                                           |
| ----------- | --------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------- |
| **Card**    | The Cash Module links your account balance or borrowing power to card spending.                                             | [Cash](/etherfi/products/cash.md)                       |
| **Markets** | Third-party decentralized exchanges and aggregators execute trades in crypto, tokenized stocks, and metals.                 | [Terms of Use](https://www.ether.fi/legal/terms-of-use) |
| **Borrow**  | An onchain lending market. Your assets are supplied to it and you can borrow against them.                                  | [Borrow](/etherfi/products/borrow.md)                   |
| **Earn**    | Liquid vaults, built on Veda or Midas infrastructure, allocate deposits across DeFi strategies and issue vault shares.      | [Earn](/etherfi/products/liquid.md)                     |
| **Send**    | Onchain transfers, plus third-party bank and payment rails.                                                                 | [Personal accounts](https://www.ether.fi/personal)      |
| **Stake**   | The ether.fi staking protocol pools ETH, runs validators through node operators, tracks rewards, and processes redemptions. | [Staking](/etherfi/products/staking.md)                 |

Each product has its own contracts, permissions, and risks. Non-custodial products can still depend on upgrade controls, roles, modules, price feeds, strategists, liquidators, bridges, and other infrastructure.

## Third-party services

The Cash card is issued by the Issuer named in your Cardholder Agreement. The Issuer and the card are not affiliated with the ether.fi protocol. Identity checks, payment rails, tokenized assets, vault infrastructure, and trading venues may also be run by third parties under their own terms.

## Where to check live details

1. **The app** shows live availability, assets, rates, balances, limits, and what your account can do.
2. **These docs** explain how each product works and its risks.
3. **The published contracts** decide how transactions execute and what the current protocol parameters are.
4. **The Terms of Use and your agreements** set the legal terms for the app, the card, and third-party services.

Do not rely on this page for a live rate, reward, collateral parameter, asset list, card benefit, or a decision about your region.

## Contracts and controls

Protocol code and contract addresses are published under [Contracts & Integrations](/etherfi/developers/contracts-and-integrations.md). Audits, multisig configurations, the trust matrix, and incident response are under [Security & Risks](/etherfi/security/security-and-risks.md).


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