KMSpico is a popular tool used to activate Microsoft products such as Windows and Office without requiring a legitimate license key. It works by emulating a Key Management Server (KMS) that provides activation services for Microsoft software. This tool is often used by individuals who are looking to bypass the activation process in order to use Microsoft products for free. However, it’s important to note that using KMSpico can be risky as it may pose security threats or violate software licensing agreements. Always ensure you are aware of the legal implications and potential risks involved when using such tools.