A digital piano is a modern electronic musical instrument with a standard piano keyboard and piano voices (often including voices other than the standard pianoforte, and often emulating MIDI voices), which are usually created by digital signal processing techniques, such as sampling.
Digital pianos are basically designed to be functionally equivalent to standard pianos, for example, they carry the standard pedals a normal piano carries, but for economy some models do without a sostenuto pedal. Digital pianos however, aurally, have some limitations (such as implementing harmonic tones on a digital piano). Digital pianos generally cannot also implement the touch of a standard piano fully.
As well as producing grand piano and upright piano sounds, many digital pianos can generate emulations of honky-tonk pianos and earlier electric pianos such as the Rhodes piano.
Some digital pianos, however, have the advantage of performing aural transposition by using the same finger positions - ie., the transposition is done transparently by the piano and not the player, as well as implementing multiple voices and timbres, mimicking different instrument with their resultant decay and sustain patterns. Digital pianos often have reverb features as well, which a standard piano cannot create on its own and exists as an effect of the room it is played in.
Typical manufacturers of digital pianos are Yamaha and Roland.