The term 'Bars on Necks' can be summarized as 'Frets', which is a five-letter word. Frets are metal bars that are placed along the neck of a guitar or other stringed instrument. They are used to create different notes and chords, and are typically made of nickel or stainless steel. Frets also help to keep the strings in tune and provide a smooth surface for the player's fingers to slide along.