What is system restore and why is it useful?

System Restore is a feature of the Windows operating system (starting with Windows ME) that allows users to restore their system to a previous point in time. This restoration includes, but is not limited to, the following types of data: system files, installed applications, the Windows registry, and system settings. As you can guess, system restores should not be taken lightly, but they can be extremely useful in the right circumstances.System Restore works by periodically creating restore points on your system. You can think of these restore points as snapshots of what your system looks like at the time. Then, using these restore points, Windows can roll back to a system state from the past. Needless to say, you can’t just jump back to any point in time – which would be incredibly useful but, for right now, implausible.