The harp is a family of string instruments which feature a number of individual strings running at an angle to its soundboard. Harp strings are plucked with the bare fingers. Harps are ancient instruments, emerging in different cultures all over the world and benefiting from technological advances. They can be categorized according to their shape and build. The most common use of the word 'harp', though, is to refer to the western pedal harp, which is a common member of the symphonic orchestra. The pedal harp is distinguished by its complex system of pedals which can alter the length of strings in order to set the whole instrument in a particular 'key'. Thus, the pedal harp functions as a fully chromatic instrument which doesn't need multiple courses, and is capable of playing uninterrupted scales at great speeds.