A powered USB hub is a hub that requires external power, in addition to drawing power from the host device. It is recommended to use a powered USB hub in the following situations:
1. When connecting power-hungry devices: Devices like external hard drives, printers, or high-powered peripherals may require more power than what the host device can supply. A powered hub ensures stable and sufficient power delivery to these devices.
2. When connecting multiple devices: If you are connecting several USB devices simultaneously, a powered hub can handle the power demands of multiple peripherals more effectively than an unpowered hub.