The HKEY_LOCAL_MACHINE, or HKLM, is part of the Windows registry, which is a database containing all computer and user information. In particular, the HKLM registry hive contains the computer settings and properties. Other registry hives such as HKEY_CURRENT_USER or HKEY_USERS contain user properties and settings. Several sub-keys exist under HKLM. The "Software" key, for example, stores all the information on applications installed on the computer. The "System" key contains all of the information about the registry itself.
Click "Start," type "regedit" in the search window and press "Enter." This opens the Windows registry editor.
Click to expand "Computer" in the left-hand pane of the registry editor.
Click to expand "HKEY_LOCAL_MACHINE."
Click to expand "System" to access all the sub-keys under it.