Throughout the 18th century, Bach was primarily valued as an organist, while his keyboard music, such as The Well-Tempered Clavier, was appreciated for its didactic qualities. The 19th century saw the publication of some major Bach biographies, and by the end of that century all of his known music had been printed. Dissemination of scholarship on the composer continued through periodicals (and later also websites) exclusively devoted to him, and other publications such as the Bach-Werke-Verzeichnis (BWV, a numbered catalogue of his works) and new critical editions of his compositions. His music was further popularised through a multitude of arrangements, including the Air on the G String and "Jesu, Joy of Man's Desiring", and of recordings, such as three different box sets with complete performances of the composer's oeuvre marking the 250th anniversary of his death.