AZW

AZW is a proprietary e-book format used by Amazon for Kindle devices and Kindle apps. It originated as a DRM-protected variant of the Mobipocket format and was adopted to distribute and protect e-books sold through Amazon’s Kindle store.

The AZW family has evolved over time. The original AZW files are DRM-protected and based on the Mobipocket technology. A later iteration, AZW3 (also known as Kindle Format 8 or KF8), introduced more advanced HTML5-based formatting and styling to support richer layouts and typography. Amazon has also introduced newer formats in the Kindle ecosystem, such as KFX, which aim to improve rendering efficiency and features, while still operating within a DRM framework. Files in the AZW family are commonly distributed with extensions such as .azw and .azw3.

Compatibility and limitations are a defining characteristic of AZW. AZW and its variants are designed for Kindle devices and official Kindle apps, and they are typically not readable by non-Kindle devices without conversion. The DRM protection further restricts copying, lending, and conversion, depending on regional and account settings. Some non-protected formats based on Mobipocket technology may be readable on other devices, but protected AZW files generally require Kindle software or authorized hardware to open.

In summary, AZW denotes a line of Amazon's Kindle e-book formats built on or derived from Mobipocket, with ongoing updates to support more complex formatting via AZW3 and related Kindle formats, all within Amazon’s DRM-enabled ecosystem.