Albinoni's famous Adagio is unusually solemn and offbeat because it wasn't, in fact, written by Tomaso Albinoni

Adagio in G Minor, attributed to 18th-century Venetian master Tomaso Albinoni, is widely familiar through its often use in movies.

However, this prominent piece is not by Albinoni at all. It is a 20th century work by Remo Giazotto who declared to have found a few-tact passage of an Albinoni composition in the archives. The fragment contained some phrases of the melody which Giazotto developed into a complete composition according to accepted Baroque rules.

So, even if it is not an Albinoni composition, it still does contain characteristics of the Italian Baroque style in its overall structure.

Some musicologists point out that Giazotto’s story for the Albioni's Adagio may be a myth, as no one other than he ever saw this fragment. Giazotto changed his story since, denying that the piece was based on Albinoni’s melody, though it was already too late: ironically, this piece has renewed Albinoni's popularity today.

Whatever the truth is, this dramatic piece will most probably forever be known as Albinoni’s Adagio. 

Here is the Adagio's masterful performance under the Herbert von Karajan's conduction:

And, of course, the loud rock version by The Doors: