KMSAuto Net is a software tool used to activate Microsoft Windows and Office products without requiring a paid license key. It works by emulating a Key Management Service (KMS) server, which tricks the software into thinking it has been officially activated. This method is typically used for volume licensing systems, but KMSAuto Net makes it accessible for individual users as well. It's popular for its simplicity, one-click activation, and ability to work offline. However, it’s important to understand that using KMSAuto Net to activate software without a legitimate license is considered software piracy and violates Microsoft's terms of service.