In the library catalog, books, videos and other materials are assigned Library of Congress (LC) subject headings based on their content. Here is a sample list of popular music-related subject headings, some of which pertain equally to books and videos (visual materials). When you view catalog records in Library Search, these subject headings display as active links pointing to other items with the same subject.
This is not an exhaustive list of subject headings pertinent to the field, but it should give you a sense of commonly used vocabulary and how subject headings are structured.