What does a piano tuner do?

What is a Piano Tuner?

A piano tuner is someone who makes minute adjustments to the tension of the strings of a piano, in order to properly align the intervals between their tones. Many factors cause pianos to be out of tune, like changes in temperature and humidity, and frequent and hard playing. A piano tuner will prevent the piano from getting damaged, as string tension is important to the health of many parts of the piano. This is different for each piano, sometimes requiring different pitches from the standard, so it is important to have regular piano tunings that help build string strength. After a few regular tunings by the piano tuner, the pitch won't stray as easily.