While different genres of music sound completely different, they all share certain similarities. Which makes it possible to mashup songs from different genres.
This video is a perfect example of that, with someone mixing Killing In the Name by Rage Against the Machine with A Thousand Miles by Vanessa Carlton.
These two songs are diametrically opposed. One is hard rock, with extreme lyrics. The other is a soft ballad, with lyrics all about love.
You wouldn’t think the two would be compatible, but somehow they fit together perfectly. The end result is a brilliant mashup which works on a number of levels.