--- title: "InMemoryDocumentStore" id: inmemorydocumentstore slug: "/inmemorydocumentstore" description: "" --- # 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.