Interior signage is a concept encompassing the study and application of visual communication systems strategically located within built environments. This academic field investigates the design, placement, function (including navigation, information dissemination, safety, and branding), and psychological impact of interior signs on human spatial understanding, behavior, and experience within diverse indoor settings. Key characteristics include their role in facilitating wayfinding, conveying critical information, reinforcing organizational identity, and enhancing the overall legibility and usability of interior spaces, making their effective integration a significant area of research in environmental psychology, architecture, and design.