Mythologies is written in two sections. The first consists of a series of essays on myths and the use of the mythic language associated with a diverse range of images in popular culture.
According to Barthes, myth is a form of signification. However myth is different from ordinary speech and language. Barthes follows de-Saussure's discussion regarding the nature of the linguistic signand he characterises myth a second class of signification.
The second section of Roland Barthes' "Mythologies", titled "Myth Today", is a theoretical discussion of Barthes' program for myth analysis which is demonstrated in the first section of Mythologies. What Barthes terms as "myth" is in fact the manner in which a culture signifies and grants meaning to the world around it. According to Barthes, anything can be a myth, and he follows this approach throughout the examples in Mythologies.
Barthes' concept of myth seems similar or at least draws on the concept of ideology as formulated by Marx in The German Ideology. Ideology according to Barthes' version in "Myth Today" is not entirely concealed and is subject for scrutiny through its cultural manifestations. These manifestations, mythologies according to Barthes, present themselves as being "natural" and are therefore transparent. What Barthes is after in his analysis of mythologies is to reveal the ideological nature of culture's underling myth.
'Semiology has taught us that much has the task of giving an historical intentional a natural justification, and making contingency appear eternal.'