The harp is a stringed instrument.

Harps were most likely independently invented in many parts of the world in remote prehistory.

The oldest depictions of harps are from 4000 B.C.E. in Egypt and 3000 B.C.E. in Persia.

Various types of harps are found in Africa, Europe, North & South America and a few parts of Asia. The 'Triangular Frame harp' is depicted in manuscripts and sculptures since the 8th century in North-West Europe.

In Germany in the second half of the 17^th century, diatonic single-row harps were fitted with manually-turned hooks which fretted individual strings to raise their pitch by a half step. In the 1700s, a link mechanism was developed connecting these hooks with pedals, leading to the invention of the single-action pedal harp. Later, a second row of hooks was installed along the neck to allow for the double-action pedal harp, capable of raising the pitch of a string by either one or two half steps. This mechanism is called the double-action pedal system, invented by Sébastien Érard in 1810.

Modern concert harp has six and a half octaves (47 strings). Harpists can tell which strings they are playing because all F strings are black or blue and all C strings are red or orange. There are seven pedals, each affecting the tuning of all strings of one letter-name, and each pedal is attached to a rod or cable within the column of the harp, which then connects with a mechanism within the neck. The pedal has three positions. In the top position no pegs are in contact with the string and all notes are flat; thus the harp's native tuning is to the scale of C-flat major. In the middle position the top wheel pinches the string, resulting in a natural, giving the scale of C major if all pedals are set in the middle position. In the bottom position another wheel is turned, shortening the string again to create a sharp, giving the scale of C-sharp major if all pedals are set in the bottom position.