# WhatsApp & SMS (One API)

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If you still use our WhatsApp RESTful API, see the relevant section in our Archive. All new WhatsApp integrations will be done via Clickatell's One API. 
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## Why use this API?

One API enables you to communicate with your mobile customers on multiple messaging channels with a single integration. Use One API to send and receive messages on both WhatsApp and SMS without the overhead of programming individual channels. 

One API also makes your implementation future-proof as we add support for additional channels to the Clickatell Platform.

## How to use this API: 

* [One API Reference](/developers-api-reference/reference/one-api.md)
* [Supported Content Types & Limitations](/developers-documentation/channels/whatsapp-and-sms-one-api/supported-content-types-and-limitations.md)
* [Status Codes & Errors](/developers-documentation/channels/whatsapp-and-sms-one-api/status-codes-and-errors.md)


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