Codes and conventions are the technical and symbolic techniques used to construct music videos. They provide a structure that is familiar and understandable to audiences. Technical codes include camera shots, editing styles, and sound elements. Symbolic codes convey hidden meanings through elements like mise-en-scene. There are different styles of music videos like narrative videos that tell a story, performance videos that feature the artist, and motif videos that use recurring themes. Codes and conventions allow audiences to identify genres and become familiar with common techniques.