I tried to learn to play the violin. 
I have always wanted to try. They are important instruments in many different genres.
How many different stringed instuments are there?
Many! Similar to the violin there is the cello, bass, and viola. The violin is the smallest and highest pitched. 
What would be the easiest to learn, maybe the viola?
Viola
The viola ( , , ) is a string instrument that is bowed or played with varying techniques. It is slightly larger than a violin and has a lower and deeper sound. Since the 18th century, it has been the middle or alto voice of the violin family, between the violin (which is tuned a perfect fifth above) and the cello (which is tuned an octave below). The strings from low to high are typically tuned to C, G, D, and A.
In the past
post-hardcore. Because of the many religious references in Flyleaf's music, they are also considered to be a Christian rock band. Despite the numerous genres they have been labeled as, May considers themselves to be simply alternative rock, adding "I think the reason we get put in different genres is because there are so many different influences in the songwriting."
As a PRS Guitar artist, Sameer Bhattacharya was interviewed in 2014 and asked about playing his PRS JA-15 with a violin bow. He shared that his musical