The Xiaomi Mi Robot Vacuum Cleaner features virtual wall technology that allows you to create virtual boundaries for the robot. This technology uses infrared sensors to create an invisible barrier that the robot cannot cross. You can use the virtual wall feature to block off certain areas of your home that you don't want the robot to enter. For example, if you have fragile items or cords on the floor, you can set up a virtual wall to prevent the robot from going near them. This ensures that the robot only cleans the areas you want it to, giving you more control over the cleaning process. The virtual wall technology is easy to set up and can be adjusted to fit your specific needs. It is a convenient feature that enhances the versatility of the Xiaomi Mi Robot Vacuum Cleaner.