Amazon Kindle reader can read PDF files natively without requiring any conversion in addition to all the common Microsoft Office formats.
To transfer PDF and other Office documents from your computer to your Kindle reader, you can connect the Kindle to the computer using the provided USB cable.
The Kindle will now appear as a separate drive in “My Computer” or “Windows Explorer.” You can drag and drop files from your computer desktop to the Kindle drive and they’ll be copied to the Kindle’s memory.
Alternatively, if you can’t get hold of the USB cable, you can send documents to Kindle wirelessly.
All Kindle users have a unique email address in the format email@example.com. Any files that you send to this email as an attachment will auto-download to your Kindle while you are in a Wi-Fi zone.
The file size of each attached document /PDF should not exceed 50MB and a single email may not have more than 25 attached documents.
If Wi-Fi is not available, you may also download files to your Kindle over 3G but Amazon will charge you a fee per download. The fee is 15 ¢ per MB while you download documents to the Kindle over 3G in the U.S. or 99 ¢ per MB when you download documents to your Kindle anywhere else in the world via 3G.