What's the difference between the Windows Management Instrumentation and the Registry?

Question

I just wanted to know if Windows Management Instrumentation uses it's own functions to get the data or is is using the Registry database.

Answer 1

WMI isn't really anything to do with or related to the registry. It is simply a way to manipulate and manage Windows machines both locally and over the network - this includes registry tasks, but it also includes a lot more.

Here is the official guide about WMI from Microsoft.

Windows Management Instrumentation (WMI) is the Microsoft implementation of Web-based Enterprise Management (WBEM), which is an industry initiative to develop a standard technology for accessing management information in an enterprise environment. WMI uses the Common Information Model (CIM) industry standard to represent systems, applications, networks, devices, and other managed components. CIM is developed and maintained by the Distributed Management Task Force (DMTF).

Answer 2

Some WMI providers use the database, others use performance counters, and others are different.

An example of the first are WMI classes that provide hardware configuration information (and, of course, the Win32_Registry class that gives you information about the registry). Many performance counters are also exposed as WMI classes (e.g. Win32_PerfFormattedData_PerfOS_System) or incorporate performance information (e.g. Win32_Process—in this case are the performance counters using WMI, visa versa, or a common underlying source).

To an extent answering this question is a guess (e.g. the Windows driver database, as used to boot Windows, is in the registry so that is the ultimate source for that information, so presumably WMI uses that). A definitive answer would requiring knowing the implementation of the WMI provider in question.