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What is the Registry?

Jul 5, 2016

The Windows Registry is a hierarchical database that contains all of the configurations and settings used by components, services, applications, and pretty much everything in Windows.

The registry has two basic concepts to be aware of: Keys and Values.

When you open the Registry Editor for the first time, you’ll see a tree view on the left-hand pane that contains all of the keys, with values on the right-hand side. It’s about as simple as an interface gets.

The root-level keys that you see on the left-hand side of the screenshot are important. Each one houses a different set of information, so depending on what you are trying to do, you’ll need to know which section to browse down into.


Windows uses this section to manage file type associations, and it is usually abbreviated HKCR when referenced in the documentation. This key is actually just a link to HKLM\Software\Classes.

You can also use this section if you want to tweak the context menu for a particular file type.


It holds the user settings for the currently logged-in user and is usually abbreviated HKCU This is actually just a link to HKEY_USERS. The most important sub-key here is HKCU\Software, which contains user-level settings for most of your software.


All of the system-wide settings are stored here, and it is usually abbreviated as HKLM. You’ll mostly use the HKLM\Software key to check machine-wide settings.


It stores all of the settings for all users on the system. You’ll typically use HKCU instead, but if you need to check settings for another user on your computer, you can use this one.


It stores all of the information about the current hardware configuration. This one isn’t used very often, and it is just a link to HKLM\SYSTEM\CurrentControlSet\Hardware Profiles\Current.