What does sync lines means?

Sync lines refer to the specific lines of dialogue or text in a script or screenplay that are intended to be synchronized with audio or visual elements, such as music, sound effects, or actions on screen. They are crucial for maintaining timing and rhythm in film, television, or theater productions, ensuring that the spoken lines align with the visual cues and enhance the overall storytelling experience. Sync lines are often highlighted or marked in scripts for easy identification by actors and production teams.