Although Schumann was not widely recognized as a composer for many years after her death, she made a lasting impression as a pianist. Trained by her father to play by ear and memorize, she gave public performances from memory as early as age thirteen, a fact noted as exceptional by her reviewers. She was one of the first pianists to perform from memory, making it the standard for concerts. She was also instrumental in changing the kind of programs expected of concert pianists. In her early career, before her marriage, she played the customary bravura pieces designed to showcase the artist's technique, often in the form of arrangements or variations on popular themes from operas, written by virtuosos such as Thalberg, Herz, or Henselt. As it was customary to play one's own compositions, she included at least one of her own works in every program, such as Variations on a Theme by Bellini (Op. 8) and the popular Scherzo (Op. 10). However, as she became a more independent artist, her repertoire contained mainly music by leading composers.