# Sinch SMS overview

Using Sinch allows you to send and receive SMS messages with a few easy steps. You can also send bulk SMS messages to multiple customers using the Sinch SMS service. This allows for timely and cost-efficient communications.

There are several methods by which you can send SMS messages using Sinch's SMS service:

- [SMS channel](/docs/conversation/channel-support/sms/) of [Conversation API](/docs/conversation/)
- [SMS SDKs](/docs/sms/sdks) in multiple languages
- [SMS REST API](/docs/sms/api-reference)
- [Sinch Enhanced SMPP service](/docs/sms/smpp)


The sections below provide summaries for the [SMS channel](/docs/conversation/channel-support/sms/) of [Conversation API](/docs/conversation/), the [SMS REST API](#sms-rest-api), and the [Sinch Enhanced SMPP service](#enhanced-smpp-service).

## SMS channel of Conversation API

The Sinch Conversation API allows you to send and receive messages globally over [SMS](/docs/conversation/channel-support/sms/). Additionally, you can send and receive messages using [RCS](/docs/conversation/channel-support/rcs/), [WhatsApp](/docs/conversation/channel-support/whatsapp/), [Viber Business](/docs/conversation/channel-support/viber-business/), [Facebook Messenger](/docs/conversation/channel-support/facebook-messenger/), and other popular channels. The API is channel agnostic, allowing you to use the same API calls to send messages over multiple different channels.

The Conversation API endpoint uses built-in transcoding gives you the power of conversation across all supported channels and, if required, full control over channel specific features.

Additionally, a single callback contains all aspects of the conversation for easy integration into the Sinch portfolio of services or any third-party platform. Conversation API is available globally with hosting locations in the US - East and the EU - Ireland, and additional channels will be supported as they become popular.

## SMS REST API

This API has a number of applications that can help you automate communications, organize your customer data, and customize messages in order to provide your customers with a more personal interaction experience.

Using this API, you can:

- [Send SMS messages](/docs/sms/api-reference/sms/batches/), to single recipients or in a batch, and view any corresponding [API callbacks](/docs/sms/api-reference/sms/webhooks/)
- [Receive SMS messages](/docs/sms/api-reference/sms/inbounds/)
- [Create and manage groups](/docs/sms/api-reference/sms/groups/), which allows for easy recipient organization and streamlined API calls
- [Review delivery reports](/docs/sms/api-reference/sms/delivery-reports/), which can provide important context into how you are reaching your customers


The SMS rest API enables all of the above through a single connection. For more information on how to use the SMS REST API, see our [Getting started guide](/docs/sms/getting-started).

Note:
If your solution is based in the US region, you may also be able to use the [SMS REST API to send mobile terminated MMS messages](/docs/sms/api-reference/mms-support). Contact support if you would like to enable this functionality on your solution.

Getting started with the SMS REST API
### SDKs in multiple languages

For developers integrating SMS functionality into their app, Sinch SDKs provide a convenient alternative to the SMS REST API.

Sinch SDKs offer a consistent standardized framework in a specific language without developers having to worry about the underlying API setup.

SDKs overview
## Enhanced SMPP service

You can send and receive messages with a granular level of control, and low latency, when using the Sinch Enhanced SMPP service. SMPP is a traditional telecoms protocol for the submission of bulk SMS; you can learn more about it at [smpp.org](https://smpp.org).

Note:
In order to use the Sinch Enhanced SMPP service, you must first reach out to Sinch's sales team, or your account manager.

Our documentation provides information on:

- [Connectivity](/docs/sms/smpp/connectivity)
- [Sending](/docs/sms/smpp/send-message) and [receiving messages](/docs/sms/smpp/receive-message)
- [Message encoding](/docs/sms/smpp/message-encoding)
- [SMPP error codes](/docs/sms/smpp/error-codes)
- [10DLC and toll-free number error codes](/docs/sms/smpp/10dlc-errors)


SMPP overview