What Is the Windows Registry?

The Windows Registry is a database of sorts that is contained in files on your hard drive. The Registry contains information about the installed programs on your computer, the operating system, hardware, and user profiles and preferences. Both Windows 2003 and Windows XP have their own unique Registry entries and files.

Numerous files comprise the Registry; however, Windows displays the contents of all of those files in a program known as the Registry Editor.

The Windows Registry is comprised of hives, keys, and subkeys. A hive is a master heading, such as HKEY_CURRENT_USER. A key is Software, and a subkey is Instant Messaging Session as defined as a custom entry type in Outlook.