Microsoft updates are always confusing. Especially when there are several files for an update whose names are only marginally different from each other. Which file is the right one?
Microsoft has been using a default pattern for all software update packets since 2003. This simplifies the search for software updates and the relevant articles in the Microsoft Knowledge Base. The basic composition of this pattern is “[Product name]-[KB article number]-[option]-[language].exe”.
Examples of names of update packets:
WindowsXP-KB123456-IA64-DEU.exe
Windows2000-KB123456-DEU.exe
WindowsServer2003-KB123456-x86-DEU.exe
The names start with the product name inclusive of version information, e.g., “Windows2000”, “WindowsXP”, “WindowsServer” or “WindowsXPTablet”. The “KB” [ “Knowledge Base” ] attribute followed by an article number refers to a relevant article in the Microsoft Knowledge Base.
The following, optional attribute is used by software manufacturers to differentiate such update packets from one another which solve the same problem on machines with different hardware configuration. These options include "x86" for 32-bit processors, "AMD64" for 64-bit AMD processors and "IA64" for 64-bit Intel processors. So now onwards you can choose the updates you want instead of downloading everything.
NOTE: More information on the terms used by Microsoft when describing updates is given in the Microsoft Knowledge Base under the article: http://support.microsoft.com/kb/824684/en-us.