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 parents keep with them. Some monitors also include video capabilities, enabling parents to see their baby as well as hear them. These devices can help parents feel more secure and attentive to their baby's needs, especially during sleep times. Many modern baby monitors come with additional features, such as temperature sensors, night vision, and two-way communication, enhancing their functionality and convenience.