diff --git a/website/web/templates/tree.html b/website/web/templates/tree.html
index 44804f21..944ff23b 100644
--- a/website/web/templates/tree.html
+++ b/website/web/templates/tree.html
@@ -278,49 +278,64 @@
     </center>
   <hr/>
   <img src="{{ url_for('static', filename='insecure.svg') }}"
-       alt="Insecure requests" height="20" width="20"> Insecure requests (HTTP)<br>
+       alt="Insecure requests" title="The node contains at least one insecure (not HTTPS) request"
+       height="20" width="20"> Unencrypted requests<br>
 
   <img src="{{ url_for('static', filename='empty.svg') }}"
-       alt="Empty responses" height="20" width="20"> Empty responses<br>
-
-  <img src="{{ url_for('static', filename='javascript.png') }}"
-       alt="JavaScript" height="20" width="20"> Javascript<br>
+       alt="Empty responses" title="This node contains only empty responses"
+       height="20" width="20"> Empty responses<br>
 
   <img src="{{ url_for('static', filename='cookie_received.png') }}"
-       alt="Cookie received" height="20" width="20"> Cookie received<br>
+       alt="Cookie received" title="Number of cookies received in the responses of this node"
+       height="20" width="20"> Cookie received<br>
 
   <img src="{{ url_for('static', filename='cookie_read.png') }}"
-       alt="Cookie read" height="20" width="20"> Cookie read<br>
+       alt="Cookie read" title="Number of cookies sent in the requests of this node"
+       height="20" width="20"> Cookie read<br>
 
   <img src="{{ url_for('static', filename='redirect.png') }}"
-       alt="Redirect" height="20" width="20"> Redirect<br>
-
-  <img src="{{ url_for('static', filename='font.png') }}"
-       alt="Font" height="20" width="20"> Font<br>
-
-  <img src="{{ url_for('static', filename='html.png') }}"
-       alt="HTML" height="20" width="20"> HTML<br>
-
-  <img src="{{ url_for('static', filename='json.png') }}"
-       alt="JSON" height="20" width="20"> JSON<br>
-
-  <img src="{{ url_for('static', filename='css.png') }}"
-       alt="CSS" height="20" width="20"> CSS<br>
-
-  <img src="{{ url_for('static', filename='exe.png') }}"
-      alt="EXE" height="20" width="20"> EXE<br>
-
-  <img src="{{ url_for('static', filename='img.png') }}"
-      alt="Image" height="20" width="20"> Image<br>
-
-  <img src="{{ url_for('static', filename='video.png') }}"
-      alt="Video" height="20" width="20"> Video<br>
+       alt="Redirect" title="Number of redirects initiated by the responses of this node"
+       height="20" width="20"> Redirect<br>
 
   <img src="{{ url_for('static', filename='ifr.png') }}"
-      alt="iFrame" height="20" width="20"> iFrame<br>
+      alt="iFrame" title="Number of resources loaded from iFrames in the responses in this node"
+      height="20" width="20"> iFrame<br>
+
+  <img src="{{ url_for('static', filename='javascript.png') }}"
+       alt="JavaScript" title="Number of JavaScript in the responses in this node"
+       height="20" width="20"> Javascript<br>
+
+  <img src="{{ url_for('static', filename='font.png') }}"
+       alt="Font" title="Number of fonts in the responses in this node"
+       height="20" width="20"> Font<br>
+
+  <img src="{{ url_for('static', filename='html.png') }}"
+       alt="HTML" title="Number of HTML in the responses in this node"
+       height="20" width="20"> HTML<br>
+
+  <img src="{{ url_for('static', filename='json.png') }}"
+       alt="JSON" title="Number of Json in the responses in this node"
+       height="20" width="20"> JSON<br>
+
+  <img src="{{ url_for('static', filename='css.png') }}"
+       alt="CSS" title="Number of CSS in the responses in this node"
+       height="20" width="20"> CSS<br>
+
+  <img src="{{ url_for('static', filename='exe.png') }}"
+      alt="EXE" title="Number of executables in the responses in this node"
+      height="20" width="20"> EXE<br>
+
+  <img src="{{ url_for('static', filename='img.png') }}"
+      alt="Image" title="Number of images in the responses in this node"
+      height="20" width="20"> Image<br>
+
+  <img src="{{ url_for('static', filename='video.png') }}"
+      alt="Video" title="Number of videos in the responses in this node"
+      height="20" width="20"> Video<br>
 
   <img src="{{ url_for('static', filename='wtf.png') }}"
-      alt="Content type not set/unknown" height="20" width="20"> Content type not set/unknown<br>
+      alt="Content type not set/unknown" title="Number of unknown resources in the responses in this node"
+      height="20" width="20"> Unknown content<br>
   </div>
   <div style="width: 70px; float: right;">
     <center>