Book excerpt: Signs in Use is an accessible introduction to the study of semiotics. All organisms, from bees to computer networks, create signs, communicate, and exchange information. The field of semiotics explores the ways in which we use these signs to make inferences about the nature of the world. Signs in Use cuts across different semiotic schools to introduce six basic concepts which present semiotics as a theory and a set of analytical tools: code, sign, discourse, action, text, and culture. Moving from the most simple to the most complex concept, the book gradually widens the semiotic perspective to show how and why semiotics works as it does. Each chapter covers a problem encountered in semiotics and explores the key concepts and relevant notions found in the various theories of semiotics. Chapters build gradually on knowledge gained, and can also be used as self-contained units for study when supported by the extensive glossary. The book is illustrated with numerous examples, from traffic systems to urban parks, and offers useful biographies of key twentieth-century semioticians.