Windows Imaging Format

Part of the benefit of the modular improvements to Windows components is the introduction of the new Windows Imaging Format (WIM), a hardware-independent format that stores images of the operating system. The premise of WIM is make images many-to-one in nature, meaning multiple images can be contained within one WIM file.

Since Windows is so modular, 95 percent of the base operating system can be replicated among any number of images, so Microsoft itself can ship just one binary image for each processor architecture -- x86 and x64 -- to everyone in the channel. Additionally, the sizes of each of the image files are reduced using single-instance storage techniques and enhanced compression.

Perhaps the best usability improvement of the WIM format is the ability to edit the image offline using standard file management tools like Windows Explorer. You can add files and folder to an image. For example, instead of the painful driver addition process in Remote Installation Services (RIS), you can simply drop drivers directly into a WIM-based image and have them automatically present. Best of all, you don't need to create independent images for each edit you make -- the additions, modifications and deletions you make can co-exist without problem in one image, reducing management burden.

Windows PE