# Welcome to the SDK Docs!

Welcome to the SDK docs!


![cosmonaut reading the cosmos docs in space](./cosmos-docs.jpg)

## Learn the SDK

### SDK Intro

If you are a newcomer and would like to learn more about the Cosmos SDK, this **[intro](./intro/README.md)** is a good starting place.

### SDK tutorial

If you like to learn by doing, you can follow the **[SDK application tutorial](https://github.com/cosmos/sdk-application-tutorial)**. It showcases how to build an SDK-based blockchain from scratch, and teaches you about the basic principles the SDK in the process.

## Use the SDK

The following sections contain the information you need if you want to build a fully-functional SDK-based blockchain:

>*NOTE*: We are currently working on improving the docs. Some info might be missing. If that is the case, try the Cosmos [Forum](https://forum.cosmos.network). Failing that, [open an issue](https://github.com/cosmos/cosmos-sdk/issues/new).

- [Introduction](./intro/README.md): Contains introductory high-level material on the Cosmos SDK.
- [Gaia](./gaia/README.md): Contains all documentation related to the gaia application (current name for the Cosmos-Hub). Also contains info on how to join gaia testnets.
- [Clients](./clients/README.md): Documentation about SDK clients like the SDK Command-Line interface and the SDK Light-client.
- [Specifications](./spec/README.md): Contains SDK and modules specifications.

If you are reading this on the Cosmos Website, please know that you can find more information on [github](https://github.com/cosmos/cosmos-sdk/tree/develop/docs). Also if you find any issues with the documentation please [*open a Pull Request*](https://github.com/cosmos/cosmos-sdk/compare?expand=1), or at least [*open an Issue*](https://github.com/cosmos/cosmos-sdk/issues/new) to update the docs!

## Cosmos Hub testnet

To install the latest version of the `gaia` application (application of the Cosmos Hub) and join the public testnet, **click [here](./gaia/join-testnet.md)**

To start your own `gaia` testnet, **click [here](./gaia/deploy-testnet.md)**

## Contribute

See [this file](https://github.com/cosmos/cosmos-sdk/blob/master/docs/DOCS_README.md) for details of the build process and
considerations when making changes.

## Version

This documentation is built from the following commit: