Fix typo.

docs/tutorial/1-serialization.md

@@ -124,7 +124,7 @@ The first part of the serializer class defines the fields that get serialized/de
 
 A serializer class is very similar to a Django `Form` class, and includes similar validation flags on the various fields, such as `required`, `max_length` and `default`.
 
-The field flags can also control how the serializer should be displayed in certain circumstances, such as when rendering to HTML. The `{'base_template': 'textarea.html'}` flag above is equivelent to using `widget=widgets.Textarea` on a Django `Form` class. This is particularly useful for controlling how the browsable API should be displayed, as we'll see later in the tutorial.
+The field flags can also control how the serializer should be displayed in certain circumstances, such as when rendering to HTML. The `{'base_template': 'textarea.html'}` flag above is equivalent to using `widget=widgets.Textarea` on a Django `Form` class. This is particularly useful for controlling how the browsable API should be displayed, as we'll see later in the tutorial.
 
 We can actually also save ourselves some time by using the `ModelSerializer` class, as we'll see later, but for now we'll keep our serializer definition explicit.