The following registry keys are located under the HKEY_LOCAL_MACHINE hive:
Note: The keys located under HKEY_LOCAL_MACHINE on your computer may differ somewhat depending on your version of Windows and your specific computer configuration.
HKEY_LOCAL_MACHINE does not actually exist anywhere on the computer, but is instead just a container for displaying the actual registry data being loaded via the subkeys located within the hive, listed above. Because of this, you, nor any program you install, can create additional keys under HKEY_LOCAL_MACHINE.
The HKEY_LOCAL_MACHINE hive is global, meaning that it's the same no matter which user on the computer views it, unlike HKEY_CURRENT_USER which is user specific.
HKEY_LOCAL_MACHINE can be accessed by opening Registry Editor and then clicking on the HKEY_LOCAL_MACHINE "folder" on the left side of the program window.