A mural in Teotihuacan, Mexico (c. 2nd century) depicting a person emitting a speech scroll from his mouth, symbolizing speech
Cuneiform is the first known form of written language, but spoken language predates writing by at least tens of thousands of years.
Two girls learning American Sign Language
Braille writing represents language in a tactile form. Language is the human capacity for acquiring and using complex systems of communication, and a language is any specific example of such a system. The scientific study of language is called linguistics. Estimates of the number of languages in the world vary between 6,000 and 7,000. However, any precise estimate depends on a partly arbitrary distinction between languages and dialects. Natural languages are spoken or signed, but any language can be encoded into secondary media using auditory, visual, or tactile stimuli, for example, in graphic writing, braille, or whistling. This is because human language is modality-independent. When used as a general concept, "language" may refer to the cognitive ability to learn and use systems of complex communication, or to describe the set of rules that makes up these systems, or the set of utterances that can be produced from those rules. All languages rely on the process of semiosis to relate signs with particular meanings. Oral and sign languages contain a phonological system that governs how symbols are used to form sequences known as words or morphemes, and a syntactic system that governs how words and morphemes are combined to form phrases and utterances. Human language has the properties of productivity, recursivity, and displacement, and it relies entirely on social convention and learning. Its complex structure affords a much wider