Anatomy of the Windows Registry

It is a directory that stores all the settings and the options for the Microsoft Windows operating system, including all of your computer's hardware, OS software, preferences, users, etc. Whenever you make a change to your control panel settings, installed software, and the like, your changes are all reflected and stored in the windows registry.

The Windows Registry has a hierarchical structure similar to other Windows files. Main folders in the registry are called "hives." Each hive contains "keys," which may contain sub-keys. Each key contains values, which is the actual information stored in the Registry. There are three types of values: string, binary, and DWORD.

The Windows Registry has six main branches.

1. HKEY_CLASSES_ROOT
This is the first branch. It is a file that associates mappings to support the drag and drop feature, OLE information, Windows shortcuts, and the Windows user interface.

2. HKEY_CURRENT_USER
This is the next branch. It contains information such as logon names, desktop settings and start menu settings.

3. HKEY_LOCAL_MACHINE
This one stores information such as the type of hardware, software and other preferences on the computer.

4. HKEY_USERS
This stores the preferences for each user on a computer.

5. HKEY_CURRENT_CONFIG
This stores information containing current hardware configurations.

6. HKEY_DYN_DATA
This contains data on the Plug and Play features on Windows, and changes every time you add new hardware.

Registry Values
Registry values are data pairs that are stored within keys. There are ten main value types.

1. The REG_SZ value is a constant string value.

2. The REG_EXPAND_SZ value is an expandable string value that contains environmental variables. These variables are replaced when called upon by an application.

3. The REG_BINARY value is a binary data value that is used for hardware component data.

4. The REG_DWORD is a DWORD value, which represents data as a 4-byte number that is used for Boolean values. The REG_DWORD_BIG_ENDIAN is another DWORD value, which uses a 32-bit integer.

5. REG_LINK is a symbolic link value used for UNICODE.

6. The REG_MULTI_SZ is a multi-string value, which is an array of strings.

7. REG_RESOURCE_LIST is a registry value that contains a resource list for device drivers.

8. The REG_FULL_RESOURCE_DESCRIPTOR value serves as a resource descriptor for the resource list value mentioned above.

9. REG_RESOURCE_REQUIREMENTS_LIST contains the resource requirements.

10. And the REG_QWORD_LITTLE_ENDIAN value is a QWORD value is a big/little-endian 64-bit integer value.

Now that you know the basic structure of the Windows Registry, you can edit the registry if you desire. Most versions of Windows contain the Registry Editor program, which is under the filename regedit.exe.

To access this file, click Start >> Run, and then type "regedit" in the text field. Now that the Registry Editor is opened you can edit the registry file. The editor is similar to Windows Explorer so you can rename, delete, and add folders the same way as you would any other file.