update doc

README.md

@@ -21,6 +21,23 @@ var dictionary = {
 }
 ```
 
+## Elements with keys
+In order to interact with the dictionary, the elements must have a specific form:
+```
+<div class="[CIRCLE OR SQUARE] [GRID LOCATION]" onclick='openDetails([KEY], this)'> 
+    <span class='box-header'>[TITLE]</span></br>
+    <span class='box-prompt'></span>
+</div>
+```
+
+Here is a complete example of this form:
+```
+<div class="circle div8" onclick='openDetails("career_community", this)'> 
+    <span class='box-header'>Career Community</span></br>
+    <span class='box-prompt'></span>
+</div>
+```
+
 
 ## Contributors