diff --git a/README.md b/README.md
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+++ b/README.md
@@ -0,0 +1,47 @@
+# flask-example
+
+A minimal web app developed in [Flask](http://flask.pocoo.org/). 
+
+The main purpose is to introduce how to implement the essential elements in web application with Flask framework, including
+
+- URL Building
+
+- Authentication with Sessions
+
+- Template & Template Inheritance
+
+- Error Handling
+
+- Integrating with *Bootstrap*
+
+- Interaction with Database (SQLite)
+
+For more basic knowledge of Flask, you can refer to [a tutorial on Tutorialspoint](https://www.tutorialspoint.com/flask/).
+
+
+## Details
+
+There are three tabs in this toy app
+
+- **Public**: this is a page which can be accessed by anyone, no matter if the user has logged in or not.
+
+- **Private**: Only logged-in user can access this page. Otherwise the user will get a 401 error page.
+
+- **Admin Page**: This part is only open to the user who logged in as "Admin". In this tab, the administrator can manage accounts (list, delete, or add).
+
+
+A few accounts were set for testing, like ***admin*** (password: admin), ***test_1*** (password: 123456), etc. You can also delete or add accounts after you log in as ***admin***.
+
+
+## References
+
+- http://flask.pocoo.org/
+
+- https://www.tutorialspoint.com/flask/
+
+
+
+## Credict
+Image private.jpg: https://commons.wikimedia.org/wiki/File:(315-365)_Locked_(6149414678).jpg
+
+Image public.jpg: https://commons.wikimedia.org/wiki/File:Drown%3F!_(131380682).jpg
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diff --git a/static/img/private.jpg b/static/img/private.jpg
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diff --git a/static/img/public.jpg b/static/img/public.jpg
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diff --git a/templates/index.html b/templates/index.html
index 4114c30..f8f6099 100644
--- a/templates/index.html
+++ b/templates/index.html
@@ -1,8 +1,18 @@
 {% extends "layout.html" %}
-{% block page_title %}Welcome to Flask Example{% endblock %}
+{% block page_title %}Welcome{% endblock %}
 {% block body %}
     {{ super() }}
 
-    <p>In this example, we cover concepts including: </p>
-    <p>template (inheritance), URL building, redirecting, error handeling, session management (authentication), etc.</p>
+    <p>This is a minimal web app developed in <a href="http://flask.pocoo.org/">Flask</a>.</p>
+    <p>The main purpose is to introduce how to implement the essentail elements in web applications with Flask framework, including</p>
+    <ul>
+        <li>URL Building</li>
+        <li>Authentication with Sessions</li>
+        <li>Template & Template Inheritance</li>
+        <li>Error Handling</li>
+        <li>Integrating with Bootstrap</li>
+        <li>Interaction with Database (SQLite)</li>
+    </ul>
+
+    <p>For more basic knowledge of Flask, you can refer to <a href="https://www.tutorialspoint.com/flask/">a tutorial on Tutorialspoint</a>.</p>
 {% endblock %}
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diff --git a/templates/layout.html b/templates/layout.html
index 322e5a1..bd68ca8 100644
--- a/templates/layout.html
+++ b/templates/layout.html
@@ -50,13 +50,13 @@
 
 <div class='container'>
 <hr>
+Developed by <a href='https://github.com/XD-DENG'>XD-DENG</a>
 <a href="http://flask.pocoo.org/"><img
    src="{{ url_for('static', filename='img/flask-powered.png') }}"
    border="0"
+   align="right"
    alt="Flask powered"
    title="Flask powered"></a>
-
-Developed by <a href='https://github.com/XD-DENG'>XD-DENG</a>
 </div>
 
 
diff --git a/templates/private_page.html b/templates/private_page.html
index 9626942..f1b71c0 100644
--- a/templates/private_page.html
+++ b/templates/private_page.html
@@ -2,5 +2,6 @@
 {% block page_title %}Private Page{% endblock %}
 {% block body %}
     {{ super() }}
+    <img src="{{ url_for('static', filename='img/private.jpg') }}" class="img-circle" alt="Cinque Terre" width="304" height="236">
     Only logged-in users, like you, can access this page.
 {% endblock %}
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diff --git a/templates/public_page.html b/templates/public_page.html
index c83b906..d716900 100644
--- a/templates/public_page.html
+++ b/templates/public_page.html
@@ -2,5 +2,6 @@
 {% block page_title %}Public Page{% endblock %}
 {% block body %}
     {{ super() }}
+    <img src="{{ url_for('static', filename='img/public.jpg') }}" class="img-circle" alt="Cinque Terre" width="304" height="236">
     You can access this no matter whether you have logged in.
 {% endblock %}
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