# Sub-domain

## Introducing sub-domain

With this new feature, by owning a Cronos ID domain (e.g. johndoe.cro), you can now create sub-domains (e.g. 1.johndoe.cro) under the parent domain!

To create a sub-domain, the owner of the parent domain just needs to assign the controller wallet address and pay the transaction fee involved.

## What is Controller?

**Controller** is the account that can manage the domain, e.g. editing domain profile, creating sub-domains. **Registrant** is the account that owns the NFT token of the domain. They can set the controller address and transfer domain ownership to another address.

For example, if you registered for johndoe.cro, you will be both the Registrant and Controller, with full control over the domain. If you create a sub-domain 1.johndoe.cro, you can assign either yourself or someone else as the controller of the domain.

## What are sub-domains for?

Sub-domains can benefit both individual users and organizations. Here are some examples:

1. Organize your wallets: 

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   You can create sub-domains like coldwallet.johndoe.cro and nft.johndoe.cro , then link to the wallet addresses serving different purposes for easier management.<br>
2. Identity for your staff or community:\
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   Sub-domains will help you create verified identities under your organization for your team or even community members.

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To learn more about how to create a sub-domain, click here.

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