Violin is one of the most expressive and unique musical instrument in a way that it’s able to imitate the human voice—which I think is the most beautiful instrument— very precisely with techniques such as vibrato, glissando and incredibly long legato lines that other instruments such as the pianos would fine it very hard or even impossible to perform. The instrument offers freedom to express emotions through a wide range of colors and dynamics. This piece by A.Piazolla perfectly demonstrate my point. The climax of this song is at around 1:34. Listen to the long legato lines but also don’t skip the intro, let it leads you there!