In order to understand why Windows has a Registry, we’ll have to go back a bit and understand what the Windows Registry started out as, and gradually transformed into what it is today.
When Windows 3.1 was introduced to the market back in March 1992, it was the first time that Microsoft implemented a “registry” with its operating system. The Windows Registry’s original purpose was to store Component Object Model (COM) information, which was ultimately tied in with the interface, and how programs would interact with each other.
At the time, many programs also used .INI files for configuration settings. When Windows 95 and Windows NT were introduced, a few new features were added to the registry, one of which was intended to eliminate the need for so many .INI files that took up a lot of cumulative space. Several other features were implemented as well, and also drastically improved how windows functioned as an operating system.
Instead of being a single provider for COM Information, the registry was now being used to configure applications, hardware, device drivers and various aspects of the operating system. It also allowed administrators to examine data on another computer over the network. Windows 95 also automatically backed up the registry in case of disaster, even though in a few rare cases, it only made matters worse, depending on the situation. Usually, the user could choose to start windows using the last good configuration. Also, a control panel was introduced that allowed administrators and users to edit specific areas of the windows registry without having to worry about accidentally mis-configuring settings.
The registry tended to change with each release of Windows. When Windows 98 was released, even more improvements and features were added to the windows registry. According to Microsoft’s own documentation, the windows registry services themselves used less memory and had improved caching support, which directly translated to faster start-up times for applications and windows itself.
Windows 98 also automatically detected registry corruption from a variety of sources and runs the registry checker to find and fix any corrupt registry entries and errors. If no problems were found, windows 98 would automatically back up the registry in addition to removing unused space in the registry, which trimmed down the size of the registry and additionally improved system performance. Since the registry could also be accessed from a central point on the network, multiple users can have personalized system settings when logging in from any computer. It should be noted that the registry setup for Windows 98 and ME are pretty much identical, whereas the registry for Windows NT4/2000 starkly different. While both registry setups were different, they performed much the same tasks. The real difference was that the NT based registry style was a bit more organized and had a lot more hierarchy.
With the advent of Windows XP, the registry underwent a hybridized style of managing data that was conducive to both Windows 98 and Windows 2000 users. The reason for this was because Microsoft wanted the transitional upgrade to their new operating system to be smooth, entirely reverse compatible, and with as few problems as possible in the process. The only way to do this was to create a system registry that handled both general releases. The windows registry still continues to change, but at this point, it now controls nearly every aspect of the Windows OS, and how it interacts with the user.