Final answer:
Babbling is the spontaneous utterance of various sounds by infants as a part of their early language and communication development, serving as the foundation for their first meaningful words.
Step-by-step explanation:
The spontaneous utterance of a variety of sounds by infants is called babbling. Initially, babies start to coo, which is a combination of a consonant and a vowel sound such as 'coo' or 'ba', and afterward they progress to babbling, repeating syllables like 'ma-ma', 'da-da', or 'ba-ba'. This babbling stage is crucial for language development and occurs even if the child is not attempting to communicate, as it can happen when the baby is alone or while interacting with others. Through this stage, babies learn to manipulate their vocal tracts and produce sounds that mimic the language spoken in their environment, which sets the foundation for their first meaningful words usually occurring between 12 to 18 months of age. Babbling is also observed in babies raised in environments where sign language is used. They show 'babbling' through hand gestures, further indicating the innate drive for language and communication development.