A standby label indicates that the product can be put into a low-power mode when not in use. This mode is often referred to as "standby mode" or "sleep mode". When a product is in standby mode, it still consumes some power, but significantly less than when in active use.
By putting a product into standby mode when not in use, you can reduce its overall power consumption and save energy. This can help to lower your electricity bills and reduce your environmental impact.