This study explores the usefulness of the two dominant schools of semiotics, the pragmatic and the structuralist, in the context of knowledge organization. Semiotics is a theoretical and methodological framework that investigates the nature of representations and how signs represent or stand for something else. Both schools of semiotics share a focus on understanding the function and basic foundations of a sign, but they differ significantly in their approach and starting point. The paper argues that the pragmatic branch's open approach to signification and unlimited semiosis is particularly useful for investigating the contextual and discursive properties of information and knowledge, while the structuralist branch's focus on semantic units, conceptual differences, and structural relationships is better suited for exploring the semantic structure of knowledge organization systems. The study hypothesizes that the structuralist view of semiotics may be advantageous for providing guiding principles for knowledge organization systems, while the pragmatic semiotic view may prove useful for analyzing knowledge communities and elucidating the prevailing theories and epistemological viewpoints. The aim of the study is to showcase the various utilities of these two semiotic approaches and enrich our understanding of knowledge organization theory.