Short answers, pulled from the story.
The violin in its present form emerged in early 16th-century northern Italy. The earliest pictures of the instrument, showing three strings, appear in Italian art around 1530, and the earliest detailed written description is from the Epitome musical by Jambe de Fer, published in Lyon in 1556.
The current record for a Stradivari violin is nine point eight million pounds, equivalent to fifteen point nine million US dollars at the time. The instrument, known as the Lady Blunt, was sold by Tarisio Auctions in an online auction on the 20th of June 2011.
The oldest surviving violin is the Charles IX, made by Andrea Amati after the French king Charles IX ordered twenty-four violins from him in 1560. It is now located in the Ashmolean Museum in Oxford.
In standard Western tuning, the four strings are tuned in perfect fifths to G3, D4, A4, and E5. In the South Indian style, the violin is typically tuned D-A-D-A, forming sa-pa pairs an octave apart, with the tonic adjusted to suit the vocalist or lead player.
Scordatura is the use of non-standard string tunings in classical music. Famous examples include Camille Saint-Saens' Danse Macabre, where the E string is tuned down for an eerie effect, and Niccolò Paganini's First Violin Concerto, where all four strings are directed to be raised a semitone.
The most prized instruments were made by the Stradivari, Guarneri, Guadagnini, and Amati families in Brescia and Cremona, Italy, and by Jacob Stainer in Austria, all active between the 16th and 18th centuries. Instruments from this era, especially those by Stradivari, Guarneri del Gesu, and Montagnana, are the most sought-after by collectors and performers today.