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For such a simple looking instrument, a guitar has a surprising number of parts to produce its sound.

Most obvious are the body and neck. But even the body is a complex piece of construction with a dozen parts or more. All of them are potentially made of different materials and come in a hundred subtly different shapes.

Slices of wood large enough to make a guitar body are expensive and hard to come by. So the body is generally constructed of two pieces each on top and botttom, with a seam down the middle. The back and top are connected by curved ribs.

The total sound is a complex combination of all the guitar parts, but it’s here that the end sound is chiefly made or broken. The quality of the body is paramount, particularly the top.

The top (often called a ‘soundboard’) is crucial, at least on an acoustic guitar, since that’s where the main vibrations are set up. As the strings vibrate, the air around them is pushed in a wave pattern.

That pattern is transferred to the top which then moves in a complicated pattern determined by the shape and material. Inside, a series of waves is set up that ultimately produces the rich sound of a good acoustic guitar.

To produce variations in that sound, the guitar has a neck with frets and a set of strings. Attached to the neck is a head with tuning pegs that allow stretching the strings to a given tension. Exactly what that tension is determines the pitch produced when a string vibrates.

But a guitar that could only produce one sound from strumming, or even the combinations of six strings, would be pretty dull. To make the infinite variety of melodies a guitar is capable of the strings are pressed down over frets – wide, low, hard material pieces set at precise distances along the neck. As the guitarist’s fingers press down on the string, clamping it to the fret, they shorten the length, which changes the pitch.

Every twelfth fret the string is shortened enough to change the pitch by one octave. Each octave change exactly doubles the frequency of vibrations, an amount of change we perceive as ‘starting over’ the series of notes.

The strings, in order, are: E-A-D-G-B-E, from the lowest pitch to the highest. So pressing down the twelfth fret on the E string produces another E, but an octave higher

The strings themselves have to be secured though, in order to vibrate rapidly enough to produce music. Everyone’s heard a very loose guitar string. It just sounds dull, because it can’t resonate properly.

Turning the tuning pegs creates part of the effect of tension. But, they have to have something in opposition to tighten against. That’s supplied by the nut and the bridge.

The nut is a bar at the base of the head (or, the top of the neck), with narrow grooves to allow the strings to pass through. It provides one end of the ‘clamp’ that keeps the strings taut.

The other end, where the string ends typically have small knobs, is the bridge. Those two points provide short, hard ridges to draw the string against, so that the tuning pegs can tighten it.

From this assembly of parts can potentially come the complex chords and notes that make the guitar one of the sweetest instruments.