> For the complete documentation index, see [llms.txt](https://developer.barchart.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developer.barchart.com/openfeed-api/streaming.md).

# Streaming API

Openfeed Streaming is a high-performance market data streaming service.

It connects your application to delayed and real-time Level 1 and Level 2 market depth. This API exchanges around the world.

Use the Streaming API when you need continuous, low-latency updates across a large symbol universe.

#### **How to Get Started with Streaming Openfeed API**:

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### Select an SDK

JAVA, .NET, and GO are available for streaming by exchange. Python  is available for data science, ops, and analytics. TypeScript/JavaScript are available for front-end interface applications. 
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### Choose an API

Streaming and REST APIs are designed to fit even the most demanding workflows. 
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### Authentication

Once Barchart's Institutional Support Team provides your credentials, you can being using our APIs
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### Metadata

Streaming API users will receive full metadata packets upon login. REST API users should review the metadata docs (see left navigation sidebar) to download all exchange-listed instrument profiles.
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### Best Practices

Before you design your system and information architecture, visit our Best Practices guide. This will help you optimize for performance and stability
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### Optimize Your Network Connection

You can request a dedicated cross-link connection or AWS PrivateLink when streaming by exchange across asset classes and global exchanges.  This can help reduce latency, the number of network hops, and bandwidth costs.
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### Working with Service Types

The Streaming API can provide the following service types: `DELAYED`, `REALTIME`, and `SNAPSHOT`. When using the `SNAPSHOT` service type, update your subscription code snippet to the relevant `REAL_TIME_SNAPSHOT` or `DELAYED_SNAPSHOT` . 
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### Working with Connection Types

Choose one of the four endpoints specifically optimized for real-time, delayed data delivery. 
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---

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