Document displayName

docs/02.1-jsx-in-depth.md

@@ -97,6 +97,9 @@ var MyComponent = React.createClass({/*...*/});
 var app = <MyComponent someProperty={true} />;
 ```
 
+JSX will infer the component's name from the variable assignment and specify
+the class's [displayName](/react/docs/component-specs.html#displayName) accordingly.
+
 See [Multiple Components](/react/docs/multiple-components.html) to learn more about using composite components.
 
 > Note:

docs/ref-03-component-specs.md

@@ -67,6 +67,15 @@ The `mixins` array allows you to use mixins to share behavior among multiple com
 <!-- TODO: Document mixins here directly. -->
 
 
+### displayName
+
+```javascript
+string displayName
+```
+
+The `displayName` string is used in debugging messages. JSX sets this value automatically, see [JSX in Depth](react/docs/jsx-in-depth.html#react-composite-components).
+
+
 ## Lifecycle Methods
 
 Various methods are executed at specific points in a component's lifecycle.