# Embedding vs Referencing — MongoDB

Source: https://www.geekswithgeeks.com/en/mongodb/mongo-embedding-vs-referencing

> Two ways to model relationships between data.

## Embedding

**Embedding** nests related data directly inside the parent document — best when the data is read together and stays small.

## Referencing

**Referencing** stores just an `_id` pointing to a document in another collection — best for large, unbounded, or independently-updated data.

## A rule of thumb

If data is always read together and won't grow unbounded — embed. If it grows large, is shared, or is updated separately — reference.