The violin played by Lieutenant Commander Data, one of several arts he pursued in his effort to understand humanity, performed in chamber concerts aboard the Enterprise-D.
Data takes up the violin as part of his study of human creativity, and his playing is technically flawless. He draws his style from recordings of great performers, and worries that it lacks anything of his own.
The instrument is seen in Elementary, Dear Data, where he plays in character as Sherlock Holmes. The Ensigns of Command opens with him preparing for a string quartet recital and warning Picard that his performance has no soul. In Sarek, a Mozart concert in which he plays moves the visiting ambassador to unexpected tears.
In Inheritance, Data performs with Juliana Tainer, the woman who helped create him, and the duet is part of how he comes to learn the truth about her.