> For the complete documentation index, see [llms.txt](https://quantinfra.gitbook.io/quantinfra-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://quantinfra.gitbook.io/quantinfra-docs/static-data/streams.md).

# Streams

A stream is an entity that defines a time series. For instance, if you receive prices for the same stock from two different data sources (e.g., different exchanges), you will need to create two streams.

Additionally, streams may be used to track time series unrelated to a particular contract (e.g., a volatility index).

<table><thead><tr><th width="217.55078125">Property</th><th>Description</th></tr></thead><tbody><tr><td>StreamId</td><td>Unique identifier</td></tr><tr><td>Ticker</td><td>Unique name</td></tr><tr><td>DatafeedId</td><td></td></tr><tr><td>ConstantStreamValue</td><td>You may use constant value streams for some time series that do not change, but must tick. For instance, instead of consuming the actual price of USDT/USD pair, you can use the constant value 1, ticking once a minute.</td></tr></tbody></table>


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