A baby monitor is a device that allows parents to listen to or watch their baby from another room. It typically consists of a transmitter unit placed near the baby and a receiver unit that the parents keep with them. Some monitors also include video capabilities, enabling parents to see their baby as well as hear them. Modern baby monitors often come with additional features such as temperature sensors, night vision, and two-way communication. These features help parents ensure their baby's comfort and safety while providing peace of mind, allowing them to attend to other tasks around the house.