# About API References

Before digging into specific API References, be sure you are familiar with the [concepts](/tutorials/concepts) and [authentication](/tutorials/authentication) quick starts.

Rhythm is divided into multiple **apps**. In the left menu, you can expand the API for any app to see the types of records that app contains.
By expanding a record type, you will find the **operations** that are available to retrieve, modify, or process records of that type.

## Try It!

You can execute mock or live API calls directly from this documentation. For more information, see the [Using Try It!](/apis/try-it) guide.

## Client Code

As you navigate the API References, sample client code will automatically be generated for each API endpoint. You can change the language of the sample
code by clicking the language drop down in the top right of any sample code block. This will change the language for all samples across all API references.

When using client code, be sure to specify your `Authorization` header as "Bearer `access_token`". If your `access_token` and `tenantId` are valid, you will receive a JSON response.