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+# Modeling Introduction 
 
+![video/gif]()
+
+## What is API Design? 
+
+Designing (also known as Modeling) your API involves describing all of the inputs and outputs across the footprint of your entire service. Your API design will answer questions like: 
+
+- What are the different resources and operations available in your API?
+- How does your API authenticate requests? 
+- What are the different data models assoicated with your service? 
+- How does your API handle errors? 
+
+## How does it fit into Stoplight? 
+
+The Stoplight design module is where you and your team will maintain the single source of truth that describes the inputs and outputs of your API. 
+
+Once you have your API described in the Stoplight design module, you can: 
+
+- Publish all or part of your API in our Documentation service 
+- Create API tests from your designs 
+- Send requests to your API to debug it 
+- ...and much more 
+
+## Getting Started 
+
+There are a few ways to get started designing your API with the Stoplight design module, depending on how developed your API is:
+
+- Create an API from scratch [Using the CRUD Builder]()
+- [Reference another API Spec]()
+- [Send HTTP Requests]() to an existing API Spec 
+- [Validate your API Spec]()