Call me fussy if you choose, but I have a few words to say regarding the use of the English word "song". All too often, particularly on Youtube but other sites as well, "song" is used to describe virtually ANY piece of music. I suppose having worked in music education I'm a bit more sensitive to this, but it is a grammatical error that's not very difficult to fix. I was going to write my own definition of the word "song", but I found the following pop up in a google search and it seems perfectly adequate:
""Piece", "Work" and "Composition" can generally be used interchangeably- both refer to any musical work, although "piece" usually connotes a less substantial musical work then "composition" does.
To be a "song", a musical work has to meet two criteria: it must have a component of singing (unless it is referred to as a "song without words", in which case it wouldn't) and it must be relatively short (an opera or a cantata would not be considered a song for this reason, although both of those pieces can be said to contain several songs). Note that a "vocalese" (which is a song without specific words- typically sung to "ah" or "ooh") can be considered a song as well.
So a song can be a piece or a composition, but not all pieces and compositions are songs."