Doc (an abbreviation of document) is a file extension for word processing documents; it is associated mainly with Microsoft and their Microsoft Word application. Historically, it was used for documentation in plain-text format, particularly of programs or computer hardware, on a wide range of operating systems. Almost everyone would have used the doc file format, whenever you write a letter, do some work or generally write on your PC you will use the doc file format. It was in the 1990s that Microsoft chose the doc extension for their proprietary Microsoft Word processing formats. As PC technology has grown the original uses for the extension have become less important and have largely disappeared from the PC world.
Early versions of the doc file format contained mostly formatted text, however development of the format has allowed doc files to contain a wide variety of embedded objects such as charts and tables from other applications as well as media such as videos, images, sounds and diagrams. doc files can also contain mail merge information, which allows a word-processed template to be used in conjunction with a spreadsheet or database.
AbiWord Apple Pages AppleWorks KWord Microsoft Word StarOffice
AZW3 - Kindle Format 8 (KF8) is Amazon's newer version of AZW. It supports HTML5 and CSS3 which were not supported through the standard AZW format. It has a number of other formatting options and is used by Amazon for all new Amazon eBooks. It is supported by fourth-generation Kindle devices running firmware version 4.1.0 or later and the Kindle Fire device.
KF8 (also called AZW3) is essentially a compiled ePub that has utlises a Palm database and Amazon's DRM scheme. It targets ePub 3 version support but existing ePub can also be used. The internal format has been decoded using mobi_unpack. The basic format remains as a PDB file similar in structure to a MOBI. More oftent than not a KF8 file will contain both a MOBI file at the beginning and the newer KF8 version of ePub later.
Kindle Fire Kindle Reader Kindle for Android Kindle for iOS