AZW, Amazon Kindle ebook file (.azw)
The AZW eBook file format
AZW is an eBook file format developed by Amazon for their device Kindle, an eBook reader. This format is used for eBooks that require DRM protection and the file format is similar to the Mobipocket PRC file which does not require any DRM protection. The AZW extension is now used for both eBook files, those that are protected with DRM and those that are not protected.
Technical details of AZW files
The AZW format is similar the MOBI format but has a higher compression rate and uses Amazon’s very own DRM protection. DRM works by restricting the usage of the AZW file to the Amazon Kindle or any other Amazon Kindle reading software. The DRM on the Kindle is locked to the device ID linked to the account at Amazon through which the device is purchased. A disadvantage of the AZW file format is, that it does not allow for series related metadata to be added to the file.