> For the complete documentation index, see [llms.txt](https://wiki.4thtech.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://wiki.4thtech.io/sdk-and-white-label/ethereum.md).

# Ethereum

Documentation for the @4thtech-sdk/ethereum package

{% hint style="info" %}
Reference for SDK 0.5.x (maintenance mode). See [Status](/sdk-and-white-label/status.md).
{% endhint %}

This package provides functionalities to interact with 4thTech protocol on Ethereum blockchain.

### Installation

```bash
npm install @4thtech-sdk/ethereum
```

### Core Classes

* [Mail](/sdk-and-white-label/ethereum/mail.md): Class that handles sending, retrieving and listening for events related to mail on-chain storage.
* [Chat](/sdk-and-white-label/ethereum/chat.md): Class that handles sending, retrieving and listening for events related to chat on-chain storage.
* [Encryptor](/sdk-and-white-label/ethereum/encryptor.md): Class that provides functionality for public key retrieval and storage, as well as shared secret key computation using the Encryptor extension.