Charles F. Hockett in the context of "Structuralism (linguistics)"

Animal languages are forms of communication between non-human animals that show similarities to human language. Animals communicate through a variety of signs, such as sounds and movements. Signing among animals may be considered a form of language if the inventory of signs is large enough, the signs are relatively arbitrary, and the animals seem to produce them with a degree of volition (as opposed to relatively automatic conditioned behaviors or unconditioned instincts, usually including facial expressions).

The current academic consensus is that animal communication systems lack key aspects that might define them as languages (or equivalent to human languages), one such aspect being humans' creation of new patterns of signs under varied circumstances. Humans routinely produce entirely new combinations of words. Some researchers, including the linguist Charles Hockett, argue that human language and animal communication differ so much that the underlying principles are unrelated. Accordingly, linguist Thomas A. Sebeok has proposed to not use the term "language" for animal sign systems. However, other linguists and biologists, including Marc Hauser, Noam Chomsky, and W. Tecumseh Fitch, assert that an evolutionary continuum exists between the communication methods of animal and human language.

Paralanguage, also known as vocalics, is a component of meta-communication that may modify meaning, give nuanced meaning, or convey emotion, by using suprasegmental techniques such as prosody, including pitch, volume, intonation, etc. It is sometimes defined as relating to nonphonemic properties only. Paralanguage may be expressed consciously or unconsciously.

The study of paralanguage is known as paralinguistics and was invented by George L. Trager in the 1950s, while he was working at the Foreign Service Institute of the U.S. Department of State. His colleagues at the time included Henry Lee Smith, Charles F. Hockett (working with him on using descriptive linguistics as a model for paralanguage), Edward T. Hall developing proxemics, and Ray Birdwhistell developing kinesics. Trager published his conclusions in 1958, 1960 and 1961.

A dialect continuum or dialect chain is a series of language varieties spoken across some geographical area such that neighboring varieties are mutually intelligible, but the differences accumulate over distance so that widely separated varieties may not be. This is a typical occurrence with widely spread languages and language families around the world, when these languages did not spread recently. Some prominent examples include the Indo-Aryan languages across large parts of India, varieties of Arabic across north Africa and southwest Asia, the Turkic languages, the varieties of Chinese, and parts of the Romance, Germanic and Slavic families in Europe. Terms used in older literature include dialect area (Leonard Bloomfield) and L-complex (Charles F. Hockett).

Dialect continua typically occur in long-settled agrarian populations, as innovations spread from their various points of origin as waves. In this situation, hierarchical classifications of varieties are impractical. Instead, dialectologists map variation of various language features across a dialect continuum, drawing lines called isoglosses between areas that differ with respect to some feature.

In linguistics, displacement is the capability of language to communicate about things that are not immediately present (spatially or temporally); i.e., things that are either not here or are not here now.

In 1960, Charles F. Hockett proposed displacement as one of 13 design features of language that distinguish human language from animal communication systems (ACSs):

Hockett's Design Features are a set of features that characterize human language and set it apart from animal communication. They were defined by the linguist Charles F. Hockett in the 1960s. He called these characteristics the design features of language. Hockett originally believed there to be 13 design features. While primate communication utilizes the first 9 features, Hockett believed that the final 4 features (displacement, productivity, cultural transmission, and duality) were reserved for humans. Hockett later added prevarication, reflexiveness, and learnability to the list as uniquely human characteristics. He asserted that even the most basic human languages possess these 16 features.

Traditional transmission (also called cultural transmission) is one of the 13 design features of language developed by anthropologist Charles F. Hockett to distinguish the features of human language from that of animal communication. Critically, animal communication might display some of the thirteen features but never all of them. It is typically considered as one of the crucial characteristics distinguishing human from animal communication and provides significant support for the argument that language is learned socially within a community and not inborn where the acquisition of information is via the avenue of genetic inheritance.

In essence, the idea of traditional transmission details the process by which language is passed down from one generation to the next. In this manner, it is often also referred to as cultural transmission where it is a mechanism of iterated learning. Common processes would include imitation or teaching. The model purports that present learners acquire the cultural behaviour, that is language in this instance by observing similar behaviours in others who acquired the language the same way. This is an important distinction made in the Scientific American The Origin of Speech, where Hockett defines traditional transmission as "the detailed conventions of any one language are transmitted extra-genetically by learning and teaching". While culture is not unique to the human species, the way it exhibits itself as language in human society is very distinctive and one key trait of this uniqueness is the element of social groups.