For the life of me this has been bugging me for years. Some mp3s I have seen are labeled something like "Artist - Song Title (main)". WHY?

I don't think I've run across this, but is it possibly due to an edited version also being available?

Main Title of movie soundtrack maybe?

Like FatTony mentioned, there's other versions of the song available like remixes. The main version is usually the original.

I've got over 50,000 mp3s, and I don't believe that I've ever seen that once. Are these from online stores, or from "other sources".

Never seen it.

Type in "main version" on a Amazon.com search for mp3s and you will see many. Mostly pop/dance/rap songs that have remix versions.

The one that gets me, is when I buy an album of music and every track is labeled with "(Album version)" at the end. Well, duh.

I've never seen it either.

This makes the most sense I guess. And to the other person who wondered. these are MP3s from "other sources"