Windows 8 is upcoming version of Microsoft Windows operating system and successor of windows 7.
Beta version of Windows 8 is now official available for download on Microsoft download center.
Microsoft has released ISO image of Windows 8 Developer Preview and is available for free download. You can now download windows 8 beta for free and try it. A fresh installation is required. No key is required during installation as key is already included in the setup.
Direct Download Link of ISO image of windows 8 Developer Preview
After download burn the iso image on a DVD or on a bootable USB / pen drive.