A guitar tuner is a device used to ensure that a guitar is in the correct pitch. It helps musicians adjust the strings to the standard notes, which are E, A, D, G, B, and E for a six-string guitar. Tuners can be electronic, clip-on, or app-based, making it easy for players to find the right sound. Using a guitar tuner is simple. The tuner detects the pitch of each string when played and indicates whether it is sharp (too high) or flat (too low). This allows guitarists to make precise adjustments, ensuring their instrument sounds harmonious during practice or performance.