Ludwig Ritter von Köchel (1800–1877) was an Austrian musicologist and composer best known for his contributions to the cataloging of Wolfgang Amadeus Mozart's works. Köchel's most significant achievement is the "Köchel Verzeichnis" (Köchel Catalogue), published in 1862, which systematically organized Mozart's compositions chronologically and assigned a unique number to each work, still in use today. Although Köchel composed a variety of works, including symphonies and chamber music, he is primarily remembered for his cataloging efforts rather than his own compositions. His meticulous approach to documenting Mozart's oeuvre had a profound impact on musicology, providing a framework for the study of classical music and influencing future cataloging methods for other composers. Köchel's work has been essential for musicians, scholars, and audiences, enabling a deeper understanding of Mozart's artistic evolution and the context of his works. His legacy continues to be felt, as the Köchel numbers are widely recognized in music literature and performance, solidifying his place in music history as a key figure in the preservation and appreciation of classical music.