Babbling is a key stage in language acquisition. We can see where it fits into the overall progression in the following “very rough” table taken from Jean Aitchison’s The Articulate Mammal: An Introduction to Psycholinguistics:
| Language stage | Beginning age |
| Crying | Birth |
| Cooing | 6 weeks |
| Babbling | 6 months |
| Intonation patterns | 8 months |
| 1-word utterances | 1 year |
| 2-word utterances | 18 months |
| Word inflections | 2 years |
| Questions, negatives | 2¼ years |
| Rare or complex constructions | 5 years |
| Mature speech | 10 years |
After the cooing or gurgling phase from which it develops, babbling has a distinctly speech-like quality because it features “sounds that are chopped up rhythmically by oral articulations into syllable-like sequences”, as Mark Liberman describes it.
The sounds most associated with babbling are mama, papa, dada, nana and slight variations thereon — as for example in the well-known video of twin babies repeating dada (and dadadadada, etc.) to each other.
This is true of a great many languages from different language families and parts of the world. The remarkable correspondence can be seen in a list included in Larry Trask’s “Where do mama/papa words come from?”, about which more below:
Posted by Stan Carey 
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