diff --git a/content/404.html b/content/404.html
new file mode 100644
index 0000000..5c10c3c
--- /dev/null
+++ b/content/404.html
@@ -0,0 +1,5 @@
+<h2>404 - Page not found</h2>
+<p>
+<a href="index.php">Back to blog</a>
+</p>
+
diff --git a/content.php b/includes/content.php
similarity index 90%
rename from content.php
rename to includes/content.php
index 91d6742..4a05be9 100644
--- a/content.php
+++ b/includes/content.php
@@ -21,6 +21,11 @@ class Page
         $this->name . "</a></li>\n");
     }
     
+    public function getFile()
+    {
+        return $this->filename;
+    }
+
     // For future-uses...
     public function getName()
     {
diff --git a/index.php b/index.php
index 6bc3122..8dd4bbf 100644
--- a/index.php
+++ b/index.php
@@ -19,7 +19,7 @@
    
 -->
 <?php
-require ("content.php");
+require ("includes/content.php");
 require ("includes/htmlcode.php");
 require ("includes/config.php");
 require ("includes/miscfunc.php");
@@ -28,6 +28,7 @@ require ("includes/miscfunc.php");
    First argument is the name of link as it should appear in the menu, second
    argument is the filename of file in content/ without directory, slashed etc.
    */
+$pageNotFound = new Page("404", "404.html");
 $aboutPage = new Page("About", "about.html");
 $contactPage = new Page("Contact", "contact.html");
 ?>
@@ -69,6 +70,8 @@ $contactPage = new Page("Contact", "contact.html");
             if (isset($_GET['content']))
             {
                 $content = $_GET['content'];
+
+                // Function to remove directories
                 function nodir($item)
                 {
                     return (!is_dir(Page::$contentFolder . $item));
@@ -78,14 +81,18 @@ $contactPage = new Page("Contact", "contact.html");
 
                 $files = (array_filter($dirContent, "nodir"));
 
+                // Iterate through all the files for a match (from ?content=)
                 foreach($files as $file)
                 {
                     preg_match_all("/[a-z_\-0-9]*/i", $file, $withoutExt);
                     if ($withoutExt[0][0] == $content)
                     {
                          include (Page::$contentFolder . $file);
+                         terminate();
                     }
                 }
+                // If no match was found, display a default page (here 404)
+                include (Page::$contentFolder . $pageNotFound->getFile());
                 terminate();
             }
             // Subpage content ends
diff --git a/stylesheet.css b/stylesheet.css
index 598e3b4..25caac6 100644
--- a/stylesheet.css
+++ b/stylesheet.css
@@ -92,13 +92,13 @@ body
 a:link
 {
     color:#000000;
-    text-decoration:none;
+    text-decoration:underline;
 }
 
 a:hover
 {
     color:#000000;
-    text-decoration:underline;
+    text-decoration:none;
 }
 
 a:visited