As YouTube has become the second largest search engine in the world, it's not surprising to see that the service has videos on everything. For instance, not only does YouTube host user-generated videos, but it also will auto generate songs that are not already on YouTube. Introduction YouTube Topic Channels.
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Google's support page says that YouTube creates “auto-generated channels” algorithms in order to “collect trending and popular videos by topic.” Google then says that “an auto-generated channel is created when we identify a topic to have a significant presence on the site. If a topic doesn't have an auto-generated channel, it may be because: there are only a few videos on the topic, there aren't many views for videos in this topic, or the videos in the topic don't meet YouTube's quality threshold.”
“As part our deals with the music industry, we've licensed their other music that wasn't yet on YouTube or didn't have a music video,” the spokesperson said for Google. “When we did that, we created auto-generated videos for them to bring their music easily to YouTube viewers everywhere. That's what you're looking at with this link you sent.” In a sense, this is what YouTube's Content ID system was designed to do. The Content ID system allows musician's to monetize their songs anywhere the song is found in any video.
So next time you're looking for a song that you're having trouble finding on YouTube's search, be sure to add “- Topic” after the song for better results. For example: “DJ Snake Magenta Riddim – Topic.”