Semantics is a study of how words, phrases, and even symbols and signs relate to one another to form structured meaning. The processing of this meaning, from a data and human language perspective, is called computational semantics. Software can use semantics to interpret sentences and create some form of output, but language often features sounds and words that can have similar meanings. Computational semantics typically focus on how to form exact meanings for phrases, often in the form of a theory.
Interpretations of phrases that make no sense can be filtered out using inference, which is sometimes used to rank the possibilities of different interpretations as well. Formulas for understanding language can be created using models, in which mathematical variables are assigned to different linguistic elements. The letters P and Q are often used with proof theory, in which formulas can be derived from others with the aid of inference rules. Computing words in a sentence sometimes helps to derive meanings or find alternative ones. In addition, mathematical calculations called algorithms are often applied to computer science, linguistics, and statistics in the field of computational semantics.
The purpose of computational semantics is to represent ambiguities, or phrases that can have different meanings, in a formulaic way. It also involves processing words that rely on context to be understood. The goal is usually to interpret a meaning automatically, as well as to relate the method of doing so, for other computational processes to be carried out more efficiently.
Computer science typically applies semantics to interpret languages, in order to understand a piece of information called an expression. Language is usually processed by computers this way; data can also be structured to represent specific information in a system. The organized meaning of language is generally applied to computer programming languages, with variables often represented as X or Y. Data on the Internet are organized in the Semantic Web, in which data models are typically implemented for structuring information online.
In addition to software programming, computational semantics is often applied to the operation of automated machinery, speech recognition systems, and Optical Character Recognition (OCR) programs. Natural language processing normally enables such systems to function efficiently. It also provides a means for humans to effectively work on computers. Software systems typically recognize the words in a sentence, or on a Web search, by understanding the speech elements and language elements that link each of them together.