Windows registry is the heart of the Windows operating system, it stores all important data for your pc. So improper changes to the registry might slow down the speed of your pc, or cause lots of issues, and what's even worse is that eventually the computer may crash on you.
But you may not know, a lot of things could change your registrywithout your permission.
When you install softwares, most of them will write a few entries to your registry, and when you uninstall them, they may not delete the entries they created. As you install and uninstall more softwares, the registry gets bigger and scattered, and will require more time to load, which will slow down the startup of Windows.
Many malware and backdoor softwares also change the registry and your computer is at stake. Oftentimes they will write to Run so that they can run automatically when you turn on your computer. And they may change your homepage, disable anything they want, and even steal your bank card or credit card code which will certainly put your money at risk.
So in order to protect your computer from damages, or just to make your computer safer and faster, it's very important to clean your registry regularly. However many people have little knowledge about registry, that's why we have to rely on registry cleaner.