Fretboard

The fretboard (also known as fingerboard) is a thing, long material. (Made out of wood) The fretboard is laminated to the top of the neck of the guitar. The fretboard is the part where the strings run over. The fretboard is also what contains the frets attached to the top of the fingerboard.

Frets
The fingerboard is fretted, having raised strips of hard material running perpendicular to the strings. When the player presses down on the strings, the strings will come into contact with the frets. Thus, causing the strings vibrations to come to a stop.

Frets may be marked by inlays to make navigating the fingerboard easier. On six-string guitars and bass guitars, markers are typically single dots that indicate the 3rd, 5th, 7th, 9th, and 12th frets. (And all the octaves following) A double dot or some other variation marks the 12th fret and 24th frets. Variations on the standard dot shape can make a guitar more distinctive. Some good examples of this are PRS guitars. Position markers are sometimes made luminescent to make them more visible on stage. Position markers are also sometimes repeated on the edge of the fingerboard for easy viewing.

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Fret Care
Over time, strings wear frets down, causing buzzing and deadening the sound. Fixing this requires a re-fretting job or fret dressing. The frets are leveled, dressed, crowned, and polished. Rarely do frets need to be replaced completely. Stainless steel guitar frets may never need to be dressed because of the density of the material. Not having frets carefully and properly aligned with the fingerboard can cause severe intonation issues and constant detuning. The best way of determining the source of a buzz and detuning problem is to measure the levelness of the frets. A straightedge positioned on the neck in the "lie" of one of the strings should show nearly level frets.