Cooing refers to the pre-linguistic or early articulated vowel-like sounds that babies produce which appear to reflect feelings of positive excitement or when they appear tobe happy and contented.

In psychology, cooing refers to the soft, vowel-like sounds made by infants as they begin to vocalize. It is an early form of communication that infants use to interact with caregivers and express their needs and emotions.

Examples of cooing sounds include "coo," "goo," and "ahh." Infants typically start cooing around 2-3 months of age and continue to do so as they develop more advanced vocal skills.

Cooing is an important part of language development, as it helps infants learn to produce and differentiate between different sounds. It also plays a crucial role in social development, as cooing and other vocalizations help infants form close relationships with caregivers and learn to interact with others.