Babbling is a stage in child development and a state in language acquisition during which an infant appears to be experimenting with uttering articulate sounds, but does not yet produce any recognizable words. Babbling begins shortly after birth and progresses through several stages as the infant's repertoire of sounds expands and vocalizations become more speech-like. Infants typically begin to produce recognizable words when they are around 12 months of age, though babbling may continue for some time afterward.

Babbling can be seen as a precursor to language development or simply as vocal experimentation. The physical structures involved in babbling are still being developed in the first year of a child's life. This continued physical development is responsible for some of the changes in abilities and variations of sound babies can produce. Abnormal developments such as certain medical conditions, developmental delays, and hearing impairments may interfere with a child's ability to babble normally. Though there is still disagreement about the uniqueness of language to humans, babbling is not unique to the human species.