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 Comparing E-books 
 ========================
 
+|app| includes an integrated e-book comparison tool that can be used to see
+what has changed inside an ebook after editing or converting it. It can compare
+books in the EPUB and AZW3 formats.
+
+To use it, either open the ebook file the tool for :ref:`edit` and then click
+:guilabel:`File->Comapre to other book` or use the :ref:`book_details` panel.
+If you do a conversion from EPUB to EPUB, the original EPUB file will be saved
+as ORIGINAL_EPUB. Simply right click ont he ORIGINAL_EPUB entry in the Book
+Details panel and choose :guilabel:`Compare to EPUB format`.
+
+The comparison tool that opens will look like the screenshot below. It shows
+you the differences in text, styles and images in the chosen books.
+
+.. image:: images/diff.png
+    :alt: The comapre tool
+    :align: center
+
+Understanding the comparison view
+----------------------------------
+
 This page is under construction.
 
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