There are two different types of harps. The celtic harp, and the pedal harp. This page is about the pedal harp. The pedal harp is the big harp out of the two, and it is called a pedal harp because sharp notes and flat notes are made by pushing the pedals on the bottom of the harp with your feet.
Harps are a very unique instruments.
Any order that you pluck the strings in sounds beautiful. Not like if you push 50 keys randomly on the piano, and that sounds really really bad. The harp will always be beautiful and it will only sound horrible if it is out of tune. The harp is a great instrument and it is a great choice if you are looking to play an instrument. The harp has been around for a long time, longer than most instruments.