Beethoven wrote 32 piano sonatas. This is just a small number when it comes to the entire collection that Beethoven put together. All told, he wrote over 130 pieces, one of which was discovered in late 2012. The piano sonatas were a different genre than many of his other works. While he stayed true to the emotions that he put into all of his works, the sonatas became the first pieces to be considered worthy of concert halls.
The first sonatas composed by Beethoven stayed true to the teachings of Mozart and Haydn, but after that, they began to take a different path. There are a few that are only four movements long, which was highly unusual for the time but encompass Beethoven perfectly.
For a musician who set out to break all the musical rules, the sonatas perfectly embrace the romantic movement. Some of the pieces were written as sets, while others were stand-alone pieces. No one is quite sure why he chose to write them this way, but they are beautiful nonetheless.