Do you play the violin? Also, the violin is also known as a fiddle.
I don't. The only string instruments I have ever tried are guitar and ukulele.
I wish I learned how to play the guitar The only thing I ever learned to play was a mandolin.
Is that played with a pick or strummed with the fingers?
It is strummed with the fingers. It has four sets of double metal strings.
What's the effect on the sound of the double strings?
THey are strung in unison to a completion of perfect fifths.
Interesting. Is that like a harp? Are they tuned in fifths?
They are tuned in fifths so one might compare it to a harp. That could be debated.
I guess Irish harps are tuned differently. I don't know much about those.