Electronic music refers to music that emphasizes the use of electronic musical instruments or electronic music technology as a central aspect of the sound of the music. Historically, electronic music was considered to be any music created with the use of electronic musical instruments or electronic processing, but in modern times, that distinction has been lost because almost all recorded music today, and the majority of live music performances, depend on extensive use of electronics. Today, the term electronic music serves to differentiate music that uses electronics as its focal point or inspiration, from music that uses electronics mainly in service of creating an intended production that may have some electronic elements in the sound but does not focus upon them. Contemporary electronic music expresses both art music forms including computer music, experimental music, musique concrète, and others; and popular music forms including multiple styles of dance music such as techno, house, trance, electro, breakbeat, drum and bass, synth pop, etc. A distinction can be made between instruments that produce sound through electromechanical means as opposed to instruments that produce sound using electronic components. Examples of electromechanical instruments are the telharmonium, Hammond organ, and the electric guitar, whereas examples of electronic instruments are a Theremin, synthesizer, and a computer.