A digital piano (not to be confused with electric piano and electronic piano), also known as piano synthesizer, portable piano, weighted keyboard, or in the late-1980s, personal electronic piano, is a modern electronic musical instrument; a variation of electronic keyboard or synthesizer designed to serve primarily as an alternative to the traditional acoustic piano, both in the way it feels to play and in the sound produced. It is intended to provide an accurate simulation of an acoustic piano. Some digital pianos are also designed to look like an acoustic piano, both the upright or grand piano body style. Digital pianos use either an electronic synthesized emulation of the piano sound or a sampled piano sound, which is then amplified through an internal loudspeaker. Digital pianos typically have weighted or semi-weighted keyboards, which attempt to recreate the feel of an acoustic piano.