What is “Indie” music? Is there something identifiable in the sound or song construction that makes it indie?
"Indie" is short for "independent," meaning music that isn't something that a major label can sell profitably. Its not that it isn't "good" music, it's just not mainstream. It tends to lean heavily toward singer/songwriters and soloists or small groups rather than full bands - though sometimes an "indie" artist will produce songs with full band accompaniment - which doesn't necessarily make them any more marketable to or by major labels. With a lot of indie music, the only thing that's different from one song or one artist to another is the words, though there are some indie instrumental artists, but not many.