
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Bach gave the title Das Wohltemperirte Clavier to a book of preludes and fugues in all 24 keys, major and minor, dated 1722, composed "for the profit and use of musical youth desirous of learning, and especially for the pastime of those already skilled in this study". The modern German spelling for the collection is Das wohltemperierte Klavier (WTK German pronunciation: ). In the composer's time, clavier referred to a variety of stringed keyboard instruments, most typically the harpsichord or clavichord, but excluding the organ, which is not a stringed keyboard. The Well-Tempered Clavier, BWV 846–893, consists of two sets of preludes and fugues in all 24 major and minor keys for keyboard by Johann Sebastian Bach. Bach Title page of Das Wohltemperierte Clavier, Book 1 (autograph)
