diff --git a/examples/context/context.go b/examples/context/context.go
index 0ad734c..3971e19 100644
--- a/examples/context/context.go
+++ b/examples/context/context.go
@@ -1,7 +1,9 @@
 // In the previous example we looked at setting up a simple
 // [HTTP server](http-servers). HTTP servers are useful for
 // demonstrating the usage of `context.Context` for
-// controlling cancellation.
+// controlling cancellation. A `Context` carries deadlines,
+// cancellation signals, and other request-scoped values
+// across API boundaries and goroutines.
 package main
 
 import (
@@ -28,6 +30,9 @@ func hello(w http.ResponseWriter, req *http.Request) {
 	case <-time.After(10 * time.Second):
 		fmt.Fprintf(w, "hello\n")
 	case <-ctx.Done():
+		// The context's `Err()` method returns an error
+		// that explains why the `Done()` channel was
+		// closed.
 		err := ctx.Err()
 		fmt.Println("server:", err)
 		internalError := http.StatusInternalServerError
diff --git a/examples/context/context.hash b/examples/context/context.hash
index 7cdacf5..5f6b83c 100644
--- a/examples/context/context.hash
+++ b/examples/context/context.hash
@@ -1,2 +1,2 @@
-5893bc5d4537db64f263a6be8efa9f2cda8ca7d8
-Elok_mfA6GV
+e338acce5d0f64d6478be4b886bd24a0fd1a3afa
+Lun5aFco3pX
diff --git a/public/context b/public/context
index a7bc320..f182bbe 100644
--- a/public/context
+++ b/public/context
@@ -30,11 +30,13 @@
             <p>In the previous example we looked at setting up a simple
 <a href="http-servers">HTTP server</a>. HTTP servers are useful for
 demonstrating the usage of <code>context.Context</code> for
-controlling cancellation.</p>
+controlling cancellation. A <code>Context</code> carries deadlines,
+cancellation signals, and other request-scoped values
+across API boundaries and goroutines.</p>
 
           </td>
           <td class="code leading">
-            <a href="http://play.golang.org/p/Elok_mfA6GV"><img title="Run code" src="play.png" class="run" /></a><img title="Copy code" src="clipboard.png" class="copy" />
+            <a href="http://play.golang.org/p/Lun5aFco3pX"><img title="Run code" src="play.png" class="run" /></a><img title="Copy code" src="clipboard.png" class="copy" />
           <div class="highlight"><pre><span class="kn">package</span> <span class="nx">main</span>
 </pre></div>
 
@@ -101,7 +103,21 @@ the work and return as soon as possible.</p>
     <span class="k">case</span> <span class="o">&lt;-</span><span class="nx">time</span><span class="p">.</span><span class="nx">After</span><span class="p">(</span><span class="mi">10</span> <span class="o">*</span> <span class="nx">time</span><span class="p">.</span><span class="nx">Second</span><span class="p">):</span>
         <span class="nx">fmt</span><span class="p">.</span><span class="nx">Fprintf</span><span class="p">(</span><span class="nx">w</span><span class="p">,</span> <span class="s">&quot;hello\n&quot;</span><span class="p">)</span>
     <span class="k">case</span> <span class="o">&lt;-</span><span class="nx">ctx</span><span class="p">.</span><span class="nx">Done</span><span class="p">():</span>
-        <span class="nx">err</span> <span class="o">:=</span> <span class="nx">ctx</span><span class="p">.</span><span class="nx">Err</span><span class="p">()</span>
+</pre></div>
+
+          </td>
+        </tr>
+        
+        <tr>
+          <td class="docs">
+            <p>The context&rsquo;s <code>Err()</code> method returns an error
+that explains why the <code>Done()</code> channel was
+closed.</p>
+
+          </td>
+          <td class="code leading">
+            
+          <div class="highlight"><pre>        <span class="nx">err</span> <span class="o">:=</span> <span class="nx">ctx</span><span class="p">.</span><span class="nx">Err</span><span class="p">()</span>
         <span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span><span class="p">(</span><span class="s">&quot;server:&quot;</span><span class="p">,</span> <span class="nx">err</span><span class="p">)</span>
         <span class="nx">internalError</span> <span class="o">:=</span> <span class="nx">http</span><span class="p">.</span><span class="nx">StatusInternalServerError</span>
         <span class="nx">http</span><span class="p">.</span><span class="nx">Error</span><span class="p">(</span><span class="nx">w</span><span class="p">,</span> <span class="nx">err</span><span class="p">.</span><span class="nx">Error</span><span class="p">(),</span> <span class="nx">internalError</span><span class="p">)</span>
@@ -189,7 +205,7 @@ cancellation.</p>
     </div>
     <script>
       var codeLines = [];
-      codeLines.push('package main\u000A');codeLines.push('import (\u000A    \"fmt\"\u000A    \"net/http\"\u000A    \"time\"\u000A)\u000A');codeLines.push('func hello(w http.ResponseWriter, req *http.Request) {\u000A');codeLines.push('    ctx := req.Context()\u000A    fmt.Println(\"server: hello handler started\")\u000A    defer fmt.Println(\"server: hello handler ended\")\u000A');codeLines.push('    select {\u000A    case \x3C-time.After(10 * time.Second):\u000A        fmt.Fprintf(w, \"hello\\n\")\u000A    case \x3C-ctx.Done():\u000A        err := ctx.Err()\u000A        fmt.Println(\"server:\", err)\u000A        internalError := http.StatusInternalServerError\u000A        http.Error(w, err.Error(), internalError)\u000A    }\u000A}\u000A');codeLines.push('func main() {\u000A');codeLines.push('    http.HandleFunc(\"/hello\", hello)\u000A    http.ListenAndServe(\":8090\", nil)\u000A}\u000A');codeLines.push('');codeLines.push('');
+      codeLines.push('package main\u000A');codeLines.push('import (\u000A    \"fmt\"\u000A    \"net/http\"\u000A    \"time\"\u000A)\u000A');codeLines.push('func hello(w http.ResponseWriter, req *http.Request) {\u000A');codeLines.push('    ctx := req.Context()\u000A    fmt.Println(\"server: hello handler started\")\u000A    defer fmt.Println(\"server: hello handler ended\")\u000A');codeLines.push('    select {\u000A    case \x3C-time.After(10 * time.Second):\u000A        fmt.Fprintf(w, \"hello\\n\")\u000A    case \x3C-ctx.Done():\u000A');codeLines.push('        err := ctx.Err()\u000A        fmt.Println(\"server:\", err)\u000A        internalError := http.StatusInternalServerError\u000A        http.Error(w, err.Error(), internalError)\u000A    }\u000A}\u000A');codeLines.push('func main() {\u000A');codeLines.push('    http.HandleFunc(\"/hello\", hello)\u000A    http.ListenAndServe(\":8090\", nil)\u000A}\u000A');codeLines.push('');codeLines.push('');
     </script>
     <script src="site.js" async></script>
   </body>