Sound design in theater creates the auditory world of a production, encompassing sound effects, music, and dialogue reinforcement. It enhances the emotional impact and supports the artistic vision, establishing setting and atmosphere while seamlessly integrating into the overall production. Key concepts include diegetic and non-diegetic sound, soundscapes, leitmotifs, and technical aspects like frequency and amplitude. Sound designers use tools such as digital audio workstations, microphones, and mixing consoles to craft a cohesive sonic experience that complements the storytelling.