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Model I/O
=========

The core element of any language model application is... the model. LangChain gives you the building blocks to interface with any language model.

![model_io_diagram](/v0.1/assets/images/model_io-1f23a36233d7731e93576d6885da2750.jpg)

[Conceptual Guide](/v0.1/docs/modules/model_io/concepts/)[​](#conceptual-guide "Direct link to conceptual-guide")
-----------------------------------------------------------------------------------------------------------------

A conceptual explanation of messages, prompts, LLMs vs ChatModels, and output parsers. You should read [this section](/v0.1/docs/modules/model_io/concepts/) before getting started.

[Quick Start](/v0.1/docs/modules/model_io/quick_start/)[​](#quick-start "Direct link to quick-start")
-----------------------------------------------------------------------------------------------------

Covers the basics of getting started working with different types of models. You should walk through [this section](/v0.1/docs/modules/model_io/quick_start/) if you want to get an overview of the functionality.

[Prompts](/v0.1/docs/modules/model_io/prompts/)[​](#prompts "Direct link to prompts")
-------------------------------------------------------------------------------------

[This section](/v0.1/docs/modules/model_io/prompts/) deep dives into the different types of prompt templates and how to use them.

[LLMs](/v0.1/docs/modules/model_io/llms/)[​](#llms "Direct link to llms")
-------------------------------------------------------------------------

[This section](/v0.1/docs/modules/model_io/llms/) covers functionality related to the LLM class. This is a type of model that takes a text string as input and returns a text string.

[ChatModels](/v0.1/docs/modules/model_io/chat/)[​](#chatmodels "Direct link to chatmodels")
-------------------------------------------------------------------------------------------

[This section](/v0.1/docs/modules/model_io/chat/) covers functionality related to the ChatModel class. This is a type of model that takes a list of messages as input and returns a message.

[Output Parsers](/v0.1/docs/modules/model_io/output_parsers/)[​](#output-parsers "Direct link to output-parsers")
-----------------------------------------------------------------------------------------------------------------

Output parsers are responsible for transforming the output of LLMs and ChatModels into more structured data. [This section](/v0.1/docs/modules/model_io/output_parsers/) covers the different types of output parsers.

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