---
title: "InMemoryDocumentStore"
id: inmemorydocumentstore
slug: "/inmemorydocumentstore"
---

# InMemoryDocumentStore

The `InMemoryDocumentStore` is a very simple document store with no extra services or dependencies.

It is great for experimenting with Haystack, however we do not recommend using it for production.

### Initialization

`InMemoryDocumentStore` requires no external setup. Simply use this code:

```python
from haystack.document_stores.in_memory import InMemoryDocumentStore

document_store = InMemoryDocumentStore()
```

### Supported Retrievers

[`InMemoryBM25Retriever`](../pipeline-components/retrievers/inmemorybm25retriever.mdx): A keyword-based Retriever that fetches documents matching a query from a temporary in-memory database.

[`InMemoryEmbeddingRetriever`](../pipeline-components/retrievers/inmemoryembeddingretriever.mdx): Compares the query and document embeddings and fetches the documents most relevant to the query.
