diff --git a/src/traits.md b/src/traits.md
index 1fc7231bf8a1..7757779a97c7 100644
--- a/src/traits.md
+++ b/src/traits.md
@@ -3,37 +3,30 @@
 Rust lets you abstract over types with traits. They're similar to interfaces:
 
 ```rust,editable
-trait Pet {
-    fn name(&self) -> String;
-}
+struct Dog { name: String, age: i8 }
+struct Cat { lives: i8 } // No name needed, cats won't respond anyway.
 
-struct Dog {
-    name: String,
+trait Pet {
+    fn talk(&self) -> String;
 }
 
-struct Cat;
-
 impl Pet for Dog {
-    fn name(&self) -> String {
-        self.name.clone()
-    }
+    fn talk(&self) -> String { format!("Woof, my name is {}!", self.name) }
 }
 
 impl Pet for Cat {
-    fn name(&self) -> String {
-        String::from("The cat") // No name, cats won't respond to it anyway.
-    }
+    fn talk(&self) -> String { String::from("Miau!") }
 }
 
 fn greet<P: Pet>(pet: &P) {
-    println!("Who's a cutie? {} is!", pet.name());
+    println!("Oh you're a cutie! What's your name? {}", pet.talk());
 }
 
 fn main() {
-    let fido = Dog { name: "Fido".into() };
-    greet(&fido);
+    let captain_floof = Cat { lives: 9 };
+    let fido = Dog { name: String::from("Fido"), age: 5 };
 
-    let captain_floof = Cat;
     greet(&captain_floof);
+    greet(&fido);
 }
 ```
diff --git a/src/traits/trait-objects.md b/src/traits/trait-objects.md
index 584c819c848c..2f57bf9fe5a4 100644
--- a/src/traits/trait-objects.md
+++ b/src/traits/trait-objects.md
@@ -3,76 +3,80 @@
 Trait objects allow for values of different types, for instance in a collection:
 
 ```rust,editable
-trait Pet {
-    fn name(&self) -> String;
-}
+struct Dog { name: String, age: i8 }
+struct Cat { lives: i8 } // No name needed, cats won't respond anyway.
 
-struct Dog {
-    name: String,
+trait Pet {
+    fn talk(&self) -> String;
 }
 
-struct Cat;
-
 impl Pet for Dog {
-    fn name(&self) -> String {
-        self.name.clone()
-    }
+    fn talk(&self) -> String { format!("Woof, my name is {}!", self.name) }
 }
 
 impl Pet for Cat {
-    fn name(&self) -> String {
-        String::from("The cat") // No name, cats won't respond to it anyway.
-    }
+    fn talk(&self) -> String { String::from("Miau!") }
 }
 
 fn main() {
     let pets: Vec<Box<dyn Pet>> = vec![
-        Box::new(Cat),
-        Box::new(Dog { name: String::from("Fido") }),
+        Box::new(Cat { lives: 9 }),
+        Box::new(Dog { name: String::from("Fido"), age: 5 }),
     ];
     for pet in pets {
-        println!("Hello {}!", pet.name());
+        println!("Hello, who are you? {}", pet.talk());
     }
 }
 ```
 
-
 Memory layout after allocating `pets`:
 
 ```bob
  Stack                             Heap
 .- - - - - - - - - - - - - -.     .- - - - - - - - - - - - - - - - - - - - - - -.
 :                           :     :                                             :
-:    pets                   :     :                                             :
-:   +-----------+-------+   :     :   +-----+-----+                             :
-:   | ptr       |   o---+---+-----+-->| o o | o o |                             :
-:   | len       |     2 |   :     :   +-|-|-+-|-|-+                             :
-:   | capacity  |     2 |   :     :     | |   | |   +---------------+           :
-:   +-----------+-------+   :     :     | |   | '-->| name: "Fido"  |           :
-:                           :     :     | |   |     +---------------+           :
-`- - - - - - - - - - - - - -'     :     | |   |                                 :
-                                  :     | |   |     +----------------------+    :   
-                                  :     | |   '---->| "<Dog as Pet>::name" |    :
-                                  :     | |         +----------------------+    : 
-                                  :     | |                                     : 
-                                  :     | |   +-+                               :   
-                                  :     | '-->|\|                               :     
-                                  :     |     +-+                               :    
-                                  :     |                                       : 
-                                  :     |     +----------------------+          : 
-                                  :     '---->| "<Cat as Pet>::name" |          : 
+:    pets                   :     :                     +----+----+----+----+   :
+:   +-----------+-------+   :     :   +-----+-----+  .->| F  | i  | d  | o  |   :
+:   | ptr       |   o---+---+-----+-->| o o | o o |  |  +----+----+----+----+   :
+:   | len       |     2 |   :     :   +-|-|-+-|-|-+  `---------.                :
+:   | capacity  |     2 |   :     :     | |   | |    data      |                :
+:   +-----------+-------+   :     :     | |   | |   +-------+--|-------+        :
+:                           :     :     | |   | '-->| name  |  o, 4, 4 |        :
+:                           :     :     | |   |     | age   |        5 |        :
+`- - - - - - - - - - - - - -'     :     | |   |     +-------+----------+        :
+                                  :     | |   |                                 :
+                                  :     | |   |      vtable                     :
+                                  :     | |   |     +----------------------+    :
+                                  :     | |   '---->| "<Dog as Pet>::talk" |    :
+                                  :     | |         +----------------------+    :
+                                  :     | |                                     :
+                                  :     | |    data                             :
+                                  :     | |   +-------+-------+                 :
+                                  :     | '-->| lives |     9 |                 :
+                                  :     |     +-------+-------+                 :
+                                  :     |                                       :
+                                  :     |      vtable                           :
+                                  :     |     +----------------------+          :
+                                  :     '---->| "<Cat as Pet>::talk" |          :
                                   :           +----------------------+          :
                                   :                                             :
                                   '- - - - - - - - - - - - - - - - - - - - - - -'
-
 ```
 
 <details>
 
-* Types that implement a given trait may be of different sizes. This makes it impossible to have things like `Vec<Pet>` in the example above.
-* `dyn Pet` is a way to tell the compiler about a dynamically sized type that implements `Pet`.
-* In the example, `pets` holds *fat pointers* to objects that implement `Pet`. The fat pointer consists of two components, a pointer to the actual object and a pointer to the virtual method table for the `Pet` implementation of that particular object.
-* Compare these outputs in the above example:
+- Types that implement a given trait may be of different sizes. This makes it
+  impossible to have things like `Vec<dyn Pet>` in the example above.
+- `dyn Pet` is a way to tell the compiler about a dynamically sized type that
+  implements `Pet`.
+- In the example, `pets` is allocated on the stack and the vector data is on the
+  heap. The two vector elements are *fat pointers*:
+  - A fat pointer is a double-width pointer. It has two components: a pointer to
+    the actual object and a pointer to the [virtual method table] (vtable) for the
+    `Pet` implementation of that particular object.
+  - The data for the `Dog` named Fido is the `name` and `age` fields. The `Cat`
+    has a `lives` field.
+- Compare these outputs in the above example:
      ```rust,ignore
          println!("{} {}", std::mem::size_of::<Dog>(), std::mem::size_of::<Cat>());
          println!("{} {}", std::mem::size_of::<&Dog>(), std::mem::size_of::<&Cat>());
@@ -80,4 +84,6 @@ Memory layout after allocating `pets`:
          println!("{}", std::mem::size_of::<Box<dyn Pet>>());
      ```
 
+[virtual method table]: https://en.wikipedia.org/wiki/Virtual_method_table
+
 </details>