How do I transfer PDF files from iBooks to my PC?

A few weeks ago, I bought some books on Amazon. I really wanted to transfer these files to my PC, so that I can read them there also.

How do you achieve this?

1. Connect your iPad to your computer.
2. Open iTunes
3. Hold the control button on your keyboard and click on the iPad in the Sidebar.
4. Click on Transfer Purchases.

Another way to do this is to open iBooks and e-mail the book to yourself.

If you have any questions, please let me know in the comments.