Updating system registry
Windows 95 and Windows NT extended its use to rationalise and centralise the information in the profusion of INI files, which held the configurations for individual programs, and were stored at various locations.
Each registry value stored in a registry key has a unique name whose letter case is not significant.
The Windows API functions that query and manipulate registry values take value names separately from the key path and/or handle that identifies the parent key.
Registry values may contain backslashes in their names, but doing so makes them difficult to distinguish from their key paths when using some legacy Windows Registry API functions (whose usage is deprecated in Win32).
The registry also allows access to counters for profiling system performance.
In simple terms, the registry or Windows Registry contains information, settings, options, and other values for programs and hardware installed on all versions of Microsoft Windows operating systems.