For example, if your baby is sleeping quietly, the monitor stays off, but as soon as your baby makes a sound, the monitor automatically "wakes up" and begins transmitting audio (and sometimes video) to your device. It's a convenient way to conserve power while still being alerted to your baby's needs.
It's particularly useful in environments where you don’t want constant noise from the monitor, but still want to be sure you're notified when something happens.
