Expression vs. Content is a series of terms used by linguist Louis Hjelmslev to rename what Ferdinand de Saussure calls signifier and signified.
For Saussure, the sign is a two-sided unit, one of the sides he calls signifier, the other – signified.
Hjelmslev further developed what is called a stratified or multilayered dyadic model of the sign (1943, 58; also Noth 1990, 67).
However, this model is discouragingly complex, as are most of Yelmslev’s ideas. But at its center is a dyadic (doubly defined) relationship between the form of expression and the form of content. This is the core of the sign according to Yelmslev. Such an understanding shows the influence of Saussure and in turn, it has influenced such contemporary semioticians as Roland Barthes and Umberto Eco.