While enrolled at Ohio State, Hockett became interested in the work of Leonard Bloomfield, a leading figure in the field of structural linguistics.

In addition to making many contributions to the field of structural linguistics, Hockett also considered such things as Whorfian Theory, jokes, the nature of writing systems, slips of the tongue, and animal communication and their relativeness to speech.

Hockett was initially receptive to Generative grammar, hailing Chomsky's Syntactic Structures as "one of only four major breakthroughs in the history of modern linguistics" (1965).

More specifically, the grammar of a language is a well-defined system by definition not more powerful than a universal Turing machine (and, in fact, surely a great deal weaker).

It is currently fashionable to assume that, underlying the actual more or less bumbling speech behavior of any human being, there is a subtle and complicated but determinate linguistic "competence": a sentence-generating device whose design can only be roughly guessed at by any techniques so far available to us.

This point of view makes linguistics very hard and very erudite, so that anyone who actually does discover facts about underlying "competence" is entitled to considerable kudos.

In the 1950s this drove some grammarians to drink and other to transformations, but both are only anodynes, not answers[8]One of Hockett's most important contributions was his development of the design-feature approach to comparative linguistics.

Hockett initially developed seven features, which were published in the 1959 paper “Animal ‘Languages’ and Human Language.” However, after many revisions, he settled on 13 design-features in the Scientific American "The Origin of Speech.

In Hockett's "The Origin of Speech", he determined that the honeybee communication system of the waggle dance holds the following design features: Gibbons are small apes in the family Hylobatidae.

These are the additional three: Cognitive scientist and linguist at the University of Sussex Larry Trask offered an alternative term and definition for number 14, Prevarication: There has since been one more Feature added to the list, by Dr. William Taft Stuart, a director of the Undergraduate Studies program at the University of Maryland: College Park's Anthropology school, part of the College of Behavioral and Social Sciences.

His “extra” Feature is: This follows the definition of Grammar and Syntax, as given by Merriam-Webster's Dictionary: Additionally, Dr. Stuart defends his postulation with references to famous linguist Noam Chomsky and University of New York psychologist Gary Marcus.

Chomsky theorized that humans are unique in the animal world because of their ability to utilize Design Feature 5: Total Feedback, or recursive grammar.

This includes being able to correct oneself and insert explanatory or even non sequitur statements into a sentence, without breaking stride, and keeping proper grammar throughout.

While there have been studies attempting to disprove Chomsky, Marcus states that, "An intriguing possibility is that the capacity to recognize recursion might be found only in species that can acquire new patterns of vocalization, for example, songbirds, humans and perhaps some cetaceans."