An electronic tuner is a device used to measure and adjust the pitch of musical instruments. It detects the frequency of a sound and displays whether it is in tune, sharp, or flat. This helps musicians, such as guitarists or pianists, ensure their instruments are accurately tuned for optimal performance. These tuners can be standalone devices or built into other equipment, like amplifiers or digital audio workstations. They often use a visual display, such as a needle or LED lights, to indicate tuning status. Electronic tuners are popular among both amateur and professional musicians for their accuracy and ease of use.