# Getting Started

To get started you can either follow along with our quickstart tutorial or you can jump directly into the API reference material.

- [Audience API](/en/api/audience-api/quickstart#treasure-data-audience-api-quickstart)
- [TD API](/en/api/td-api/quickstart)
- [Client Library REST APIs](/en/api/td-api/td-client)
- [Postback API](/en/api/postback/quickstart)
- [System APIs](/en/api/system-api/system_api)


## About REST APIs

Representational State Transfer (REST) defines a set of architectural principles by which you can design Web services that focus on systems’ resources and how these resource states are addressed and transferred over HTTP by client applications written in different languages. REST requires that a client make a request to the server to retrieve or modify data on the server. A request generally consists of:

- an HTTP verb, which defines what kind of operation to perform
- a header, which allows the client to pass along information about the request
- a path to a resource
- an optional message body containing data


The basic HTTP verbs to interact with resources in a REST system are

- GET — retrieve a specific resource (by id) or a collection of resources
- POST — create a new resource
- PUT/PATCH — update a specific resource (by id)
- DELETE — remove a specific resource by id


| Operation HTTP | REST | SQL Equivalent |
|  --- | --- | --- |
| Create a resource on the server | POST | INSERT |
| Retrieve a resource | GET | SELECT |
| Update or change a resource state | PUT/PATCH | UPDATE |
| Remove or delete a resource | DELETE | DELETE |


## Choosing Your Data Import Method

There are various ways to bring your data into Treasure Data. Depending on the format of your data, or the languages you are using, you might consider several options.

If no solution is found in the [client libraries](/en/api/td-api/td-client), you might need to write a client for one of the following APIs that corresponds to the programming language or data format you are using.

There are several Public Import APIs available in each region. The API you use will depend on your data format and the [sites and endpoints for your region](/en/overview/aboutendpoints#treasure-data-api-baseurls).

## Determine Your Import API Method

1. Select your data format from one of the following.
  - **msgpack** — You can use the [Treasure Data Import API](/en/api/system-api/bulk_import_api) if you have batches of data in gzipped  [msgpack](https://www.msgpack.org) format or you are using [fluentd](https://www.fluentd.org). This API is also known as the "Stream Import" API, and uses `api-import` subdomain.
Most client libraries—as well as td-agent, td toolbelt, and fluentd collector daemon—use this API.
  - **JSON** — You can use the [Postback API](/en/api/postback/quickstart) if you have small batches of JSON format data. This API is also known as the "JS/ Mobile SDK/ Postback" API and uses the `in` subdomain. It expects frequent, small payloads. The [JavaScript](/en/sdk/js-sdk/quickstart), [Android](/en/sdk/android-sdk/quickstart), and [iOS](/en/sdk/ios-sdk/quickstart) SDKs use this API.
  - **Other External Systems or Formats** — If your data is held by a third party, accessed by API or via file export, you can use the [Treasure Data Bulk Import API](/en/api/system-api/bulk_import_api). This API combines the `api` subdomain and `v3/bulk_import/*` paths. Treasure Data’s [embulk-based](https://www.embulk.org) integrations use this API. Learn more about Treasure Data’s powerful [integrations](https://docs.treasuredata.com/display/PD/Integrations).
2. Choose the appropriate baseURL from a list of [Sites and Endpoints](/en/overview/aboutendpoints#treasure-data-api-baseurls).