Registry keys are essential system components that store settings for a computer's operating system. This includes critical OS functions and options for installed applications as well as user preferences. Registry keys are organized in a hierarchy of folders containing keys for specific system functions. Windows contains a set of predefined keys listed as the following:
Registry key categories
HKEY_CURRENT_USER - contains configuration for the current user
HKEY_USERS - contains all active user profile information
HKEY_LOCAL_MACHINE - contains configuration information for the computer
HKEY_CLASSES_ROOT - acts as a subkey for HKEY_LOCAL_MACHINE to control system preferences
HKEY_CURRENT_CONFIG - contains information on the system's hardware
To access the Registry Editor, go to Start -> Run, then type in 'regedit'. In the Registry Editor window, click on the + to expand the folder options. Keys can be exported for backup or imported from a backup, and their permissions modified to control read/write access.
Go to Microsoft Support for more specific information on editing registry keys safely.
WARNING: Before modifying the registry, back up your entire system first. Corrupt or damaged registry files can lead to an unstable operating system or total system failure.
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