[2] The body of the harp consists of a straight upright pillar, sometimes adorned with a crown at the top; a soundboard, which in most harps is pear-shaped with additional width at the bottom, although some older instruments have soundboards that are straight-sided but widening toward the bottom; a harmonically curved neck containing the mechanical action made up of over 1,400 parts; and a base with seven pedals.

Earlier pedal harps had a single-action mechanism that provided only sharped notes, the first of which was made in 1720 by Jacob Hochbrucker in Bavaria.

In the middle position, the top disc's pins press against the string, resulting in natural notes and giving the scale of C♮ major if all pedals are used.

In the bottom position, the second, lower disc operates, shortening the string again to create a sharp and giving the scale of C♯ major if all pedals are used.

Madame de Genlis, for example, in her Méthode, published in Paris in the early 19th century, promotes the use of all fingers,[6] while Roslyn Rensch suggests that Mlle de Guînes, the harpist for whom Mozart wrote his Concerto for Flute and Harp, might occasionally have used all five fingers when playing the harp.

[7] In more modern music, the little finger is used very rarely, for example in simultaneous cluster chords, such as in Daniel Kessner's Sonatina.

Tone is also affected by the skin of the harpist, how much oil and moisture it contains, and the amount of thickening by callus formation and its surface texture.

The differences between the French schools lie in the posture of the arms, shape of the hand, and musical aesthetics.

The traditional French schooling lets the player lightly rest the right arm against the harp, using the wrist to sometimes bring the hand only away from the string.

Salzedo's technique generally calls for the arms to be held horizontally[9] and emphasizes the role of aesthetic hand and arm gestures after the string has been plucked: "Each of the thirty-seven tone colors and effects of the harp calls for a gesture corresponding to its sonorous meaning.

"[10] The harp found its early orchestral use as a solo instrument in concerti by many baroque and classical composers (Händel, Mozart, Boieldieu, Albrechtsberger, Schenk, Dussek, Spohr) and in the opera houses of London, Paris and Berlin and most other capitals.

Hector Berlioz began to use it in symphonic music, but he found performances frustrating in countries such as Germany, which had few harps or sufficiently proficient harpists.

Dorothy Ashby (whose work is often sampled by hip hop artists), Brandee Younger and Alice Coltrane[11] are other jazz harpists.

In the 1970s, harp parts were common in popular music, and can be heard in such hits as Cher's "Dark Lady" and "Gypsies, Tramps & Thieves", as well as "Boogie Nights" by Heatwave.

A pedal harpist, Ricky Rasura, is a member of the "symphonic pop" band, The Polyphonic Spree.

Philadelphia based Indie Pop Band Br'er uses a pedal harp as the foundation for their cinematic live sets.

Art in America was the first known rock band featuring a pedal harp to appear on a major record label, released in 1983.

The pedal harp was also present in the Michael Kamen and Metallica concert and album, S&M, as part of the San Francisco Symphony orchestra.

R&B singer Maxwell featured harpist Gloria Agostini in 1997 on his cover of Kate Bush's "This Woman's Work".

On his 7th solo album Finding Forever, hip-hop artist Common features harpist Brandee Younger on the introductory track, followed by a Dorothy Ashby sample from her 1969 recording of "By the Time I Get to Phoenix".

Some Celtic-pop crossover bands and artists such as Clannad and Loreena McKennitt include folk harps, following Alan Stivell's work.