A harp is a stringed instrument which has the plane of its strings positioned perpendicular to the soundboard. It is classified as a chordophone by the Harvard Dictionary of Music and only types of harps are in that class of instruments with plucked strings. All harps have a neck,resonator, and strings. Some, known as frame harps, also have a forepillar; those lacking the forepillar are referred to as open harps. Depending on its size (which varies considerably), a harp may be played while held in the lap or while it stands on the floor. Harp strings are made ofnylon, gut, wire, or silk on certain instruments. A person who plays the harp is called a harpist or harper. Folk musicians often use the term "harper", whereas classical musicians use "harpist".
Various types of harps are found in Africa, Europe, North, and South America, and in Asia. In antiquity, harps and the closely related lyres were very prominent in nearly all cultures. The oldest harps found thus far have been uncovered in ruins from ancient Sumer. The harp also predominant in the hands of medieval bards, troubadors and minnesingers, as well as throughout the Spanish Empire. Harps continued to grow in popularity through improvements in their design and construction through the beginning of the twentieth century.
The aeolian harp (wind harp), the autoharp, and all forms of the lyre and Kithara are not harps because their strings are not perpendicular to the soundboard; they are part of the zither family of instruments along with the piano and harpsichord. In blues music, the harmonica is called a "Blues harp" or "harp", but it is a free reed wind instrument, not a stringed instrument, and is therefore not an actual harp.