Musical composition for solo instrument and orchestra. The solo concerto grew out of the older concerto grosso. Giuseppe Torelli's violin concertos of 1698 are the first known solo concertos. Antonio Vivaldi, the first important concerto composer, wrote more than 350 solo concertos, mostly for violin. Johann Sebastian Bach wrote the first keyboard concertos. From the Classical period on, most concertos have been written for piano, followed in popularity by the violin and then the cello. Wofgang Amadeus Mozart wrote 27 piano concertos; other notable composers of piano concertos include Ludwig van Beethoven, Felix Mendelssohn, Frédéric Chopin, Franz Liszt, and Johannes Brahms. From the outset the concerto has been almost exclusively a three-movement form, with fast tempos in the first and third movements and a slow central movement. It has generally been intended to display the soloist's virtuosity, particularly in the unaccompanied and often improvised cadenzas near the ends of the first and third movements. Nineteenth-century concertos were often conceived as a kind of dramatic struggle between soloist and orchestra; many later composers preferred that the soloist blend with the orchestra.