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docs/redis_modules.md

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+# Redis Modules
+
+Some advanced features of Redis OM, like rich query expressions and saving data as JSON, rely on core features from two source available Redis modules: **RediSearch** and **RedisJSON**.
+
+These modules are the "magic" behind the scenes:
+
+* RediSearch adds querying, indexing, and full-text search to Redis
+* RedisJSON adds the JSON data type to Redis
+
+## Why this is important
+
+Without RediSearch or RedisJSON installed, you can still use Redis OM to create declarative models backed by Redis.
+
+We'll store your model data in Redis as Hashes, and you can retrieve models using their primary keys. You'll also get all the validation features from Pydantic.
+
+So, what won't work without these modules?
+
+1. Without RedisJSON, you won't be able to nest models inside each other, like we did with the example model of a `Customer` model that has an `Address` embedded inside it.
+2. Without RediSearch, you won't be able to use our expressive queries to find models -- just primary keys.
+
+## So how do you get RediSearch and RedisJSON?
+
+You can use RediSearch and RedisJSON with your self-hosted Redis deployment. Just follow the instructions on installing the binary versions of the modules in their Quick Start Guides:
+
+- [RedisJSON Quick Start - Running Binaries](https://oss.redis.com/redisjson/#download-and-running-binaries)
+- [RediSearch Quick Start - Running Binaries](https://oss.redis.com/redisearch/Quick_Start/#download_and_running_binaries)
+
+**NOTE**: Both Quick Start Guides also have instructions on how to run these modules in Redis with Docker.
+
+Don't want to run Redis yourself? RediSearch and RedisJSON are also available on Redis Cloud. [Get started here.](https://redis.com/try-free/)