What is Formal Semantics?

  1. Some definitions.
    Formal semantics is the study of the semantics of formal and also natural languages. A formal language can be defined apart from any interpretation of it. This is done by designating a set of symbols (also called an alphabet) and a set of formation rules (also called a formal grammar) which determine which strings of symbols are well-formed formulas. When transformation rules (also called rules of inference) are added, and certain sentences are accepted as axioms (together called a deductive system or a deductive apparatus) a logical system is formed. An interpretation is an assignment of meanings to these symbols and truth-values to its sentences [1].
    In theoretical computer science, formal semantics is the field concerned with the rigorous mathematical study of the meaning of programming languages and models of computation. The formal semantics of a language is given by a mathematical model that describes the possible computations described by the language [2].
  2. It's the name of this website.

References

[1] The Cambridge Dictionary of Philosophy, Formal semantics.

[2] Wikipedia, Formal semantics of programming languages.