A synthesizer is an electronic musical instrument that generates audio signals to create sounds. It can imitate traditional instruments or produce entirely new sounds through various methods, such as subtractive synthesis, additive synthesis, and frequency modulation. Synthesizers often feature a keyboard interface, allowing musicians to play melodies and chords. These instruments can be found in various forms, including analog synthesizers, which use voltage-controlled circuits, and digital synthesizers, which rely on computer algorithms. Many synthesizers also include built-in effects and sequencers, enabling users to manipulate sounds and create complex musical compositions. They are widely used in genres like electronic, pop, and film music.