Semiotics, semiotic studies, or semiology is the study of sign processes (semiosis), or signification and communication, signs and symbols, both individually and grouped into sign systems. It includes the study of how meaning is constructed and understood.

The field was most notably formalized by the Vienna Circle and presented in their International Encyclopedia of Unified Science, in which the authors agreed on breaking out the field, which they called "semiotic", into three branches: