diff --git a/db.sqlite3 b/db.sqlite3
index 3642fec..beb94b8 100644
Binary files a/db.sqlite3 and b/db.sqlite3 differ
diff --git a/three_d_viewer/__init__.py b/three_d_viewer/__init__.py
index e69de29..fd4d95c 100644
--- a/three_d_viewer/__init__.py
+++ b/three_d_viewer/__init__.py
@@ -0,0 +1,3 @@
+"""
+Define three_d_viewer as a package
+"""
diff --git a/three_d_viewer/admin.py b/three_d_viewer/admin.py
index d98e024..efe0b95 100644
--- a/three_d_viewer/admin.py
+++ b/three_d_viewer/admin.py
@@ -1,5 +1,9 @@
+"""
+Configuration for the Django admin site
+"""
+
 from django.contrib import admin
-from three_d_viewer.models import Category, Sample, Question, Answer
+from models import Category, Sample, Question, Answer
 
 admin.site.register(Category)
 admin.site.register(Sample)
diff --git a/three_d_viewer/ajax.py b/three_d_viewer/ajax.py
index 290b456..1c31d8b 100644
--- a/three_d_viewer/ajax.py
+++ b/three_d_viewer/ajax.py
@@ -1,18 +1,20 @@
+"""
+Handle asynchronous calls from the web pages
+"""
+
 from django.utils import simplejson
 from dajaxice.decorators import dajaxice_register
 
-from three_d_viewer.models import Question
-
-
-@dajaxice_register
-def dajaxice_example(request):
-    test = check_answer(request, 3, 1)
-    print test
-    return simplejson.dumps({'message': 'Hello from Python!'})
+from models import Question
 
 
 @dajaxice_register
 def check_answer(request, answerid, questionid):
+    """
+    Check whether answerid is the correct answer for questionid.
+    Returns a boolean in 'result'
+    """
+
     question = Question.objects.get(id=int(questionid))
 
     result = False
@@ -20,5 +22,5 @@ def check_answer(request, answerid, questionid):
         print type(answer.id)
         if answer.id == int(answerid):
             result = True
-    print simplejson.dumps({'result': result})
+
     return simplejson.dumps({'result': result})
diff --git a/three_d_viewer/models.py b/three_d_viewer/models.py
index d681324..e855732 100644
--- a/three_d_viewer/models.py
+++ b/three_d_viewer/models.py
@@ -1,7 +1,15 @@
+"""
+Defines the models that that Django application uses
+"""
+
 from django.db import models
 
 
 class CommonInfo(models.Model):
+    """
+    Common base class for models that need a name and active field. It is
+    intended to be an abstract class.
+    """
     name = models.CharField(max_length=100)
     active = models.BooleanField(default=True)
 
@@ -9,16 +17,27 @@ class CommonInfo(models.Model):
         return self.name
 
     class Meta:
+        """
+        Declare the class as abstract
+        """
         abstract = True
 
 
 class Category(CommonInfo):
+    """
+    Contains the details for a category of samples. Categories have a parent
+    category field to another category which creates a tree structure.
+    """
     parent = models.ForeignKey('self', blank=True, null=True,
                                on_delete=models.SET_NULL,
                                related_name='children')
 
 
 class Sample(CommonInfo):
+    """
+    The definition of a model itself. The model_filename is the path relative
+    to the models directory.
+    """
     model_filename = models.CharField(max_length=1000)
     description = models.CharField(max_length=2000, default='', blank=True,
                                    null=True)
@@ -27,10 +46,16 @@ class Sample(CommonInfo):
 
 
 class Question(models.Model):
+    """
+    The definition of a multiple choice question, associated with a Sample
+    """
     text = models.CharField(max_length=2000)
     sample = models.ForeignKey(Sample, related_name='questions')
 
     def correct_answers(self):
+        """
+        Return a list of correct answers to the question
+        """
         return self.answers.filter(correct=True)
 
     def __unicode__(self):
@@ -38,6 +63,9 @@ class Question(models.Model):
 
 
 class Answer(models.Model):
+    """
+    The definition of an answer to a Question
+    """
     text = models.CharField(max_length=2000)
     correct = models.BooleanField(default=False)
     question = models.ForeignKey(Question, related_name='answers')
diff --git a/three_d_viewer/views.py b/three_d_viewer/views.py
index 666d11d..290b73b 100644
--- a/three_d_viewer/views.py
+++ b/three_d_viewer/views.py
@@ -1,7 +1,8 @@
+"""
+Define the views for the Django MVC
+"""
+
 from django import template
-from django.shortcuts import get_object_or_404, render
-from django.http import HttpResponseRedirect, HttpResponse
-from django.core.urlresolvers import reverse
 from django.views import generic
 
 from three_d_viewer.models import Sample
@@ -15,6 +16,9 @@ def children_tag(category):
 
 
 class IndexView(generic.ListView):
+    """
+    Define the page to display the Sample objects that can be viewed
+    """
     template_name = 'three_d_viewer/index.html'
     context_object_name = 'active_samples'
 
@@ -26,5 +30,8 @@ class IndexView(generic.ListView):
 
 
 class DetailView(generic.DetailView):
+    """
+    Define the view to view the 3D model of a sample
+    """
     model = Sample
     template_name = 'three_d_viewer/detail.html'