The guitar has a lot of components with a wide range of variety and forms. Additionally, there are also some differences between the parts of an electric versus the parts of acoustic guitars.
This article will introduce you to the parts of an acoustic guitar, their function, and some different variants you might encounter.
Anatomy of an Acoustic Guitar
Like most string instruments like the ukulele, banjo, or mandolin, there are also three main parts to an acoustic guitar.
This is the case for every type of guitar so let’s take a look at each of them in a bit more detail.
The Headstock (Head)
One of three main areas of the guitar is the headstock, commonly just called the head.
This is at the top of the guitar, as far from the body as you can get, and is one of two places where the strings are attached to the instrument.
Tuning Pegs (Tuning keys, Tuners, Tuning heads)
The tuning pegs are those things that stick out of the head.
They are usually made of metal and can be arranged three on each side of the head (e.g. on a Les Paul) or all six on one side (e.g. Fender Stratocaster).
As you can probably guess they are used to tune the strings! Turning one of them will make a string tighter, which raises the pitch, or looser, which lowers the pitch.
Sometimes you will hear machine heads used synonymously with tuning pegs.
Other times it is used to refer to the entire tuning mechanism rather than just the pegs which stick out.
Besides the pegs, tuning machines are composed of a pinion gear, worm gear, and string post (see below).
Depending on your guitar, the gears may be exposed (common on older instruments and classical guitars) or placed inside a casing with lubrication to protect them from wear and tear (common on instruments made after about 1950).
Capstan (String Post, Tuning Post)
The parts of the machine head (tuning mechanism) which physically holds the strings are called capstans.
You can see them sticking out perpendicular to the head.
Impress your friends with that fairly unknown term!
Moving away from tuners, the nut is the thin piece of material placed where the headstock meets the fretboard.
Nuts are usually wood or plastic but could also be ebony, ivory, or other material.
Nuts are slotted and their purpose is to seat the strings at one end of their vibrating length.
Deepening the slots can lead to lower string action but that is a pretty uncommon problem and enlarging the slots should only be done by a professional luthier (guitar maker).
One thing you can do is make sure the grooves on the nut are smooth.
Otherwise you risk nicking and breaking a string!
Another part you can access through the head is the truss rod.
This rod, usually steel, runs through the neck and stabilizes the curvature (also called relief) of the neck to keep it from bending due to pressure caused by the strings.
Truss rods can be adjusted to change the rigidity in the guitar neck and influence string action but I’d leave that procedure to a professional!
Also, note that classical (nylon-string) guitars do not have truss rods.
The neck of a guitar is the long wooden board underneath the strings.
The shape of the curve of the neck can vary but the three main types you will encounter are C-shape, U-shape, and V-shape.
The shape affects the feel as you play but is not adjustable (unless you completely swap out a new bolt-on neck).
In addition to different shapes, there are different ways to attach the neck to the body of the guitar: the three main ways are Bolt-On, Neck-Through, and Set.
Bolt-on necks are screwed onto the body right where they meet, neck-through necks, neck-through (neck-thru) necks run the entire length of the guitar’s body, and set necks, common for acoustics but uncommon for electrics, are glued onto the body.
Heel (Neck Joint)
The heel is where the neck meets the body of the guitar.
If you flip your guitar over, you should be able to see it jutting out below the bottom of the neck.
The fingerboard is where you press the strings down to play notes.
They are usually made out of rosewood or maple and generally maple will provide a brighter sound.
Since you have direct contact with the fingerboard it’s an important part of the instrument in terms of both feel and sound.
Frets are the raised metal wires that run across the fingerboard.
They allow the string to be shortened when you press down on the string in a way that corresponds to exact half notes.
Frets mean that the instrument acts like the fixed keys of a piano and, unlike with violins or other unfretted instruments, guitarists don’t have to manually find the exact spot on the neck for a specific pitch.
Frets come in different sizes, from ‘jumbo’ to small, and the size affects the feel of playing.
Generally, jumbo frets are easier to play but, unlike with smaller frets, your fingers won’t actually touch the fingerboard, which some players prefer.
Position Markers (Inlays, Inlay Markers)
Almost all non-classical guitars have inlaid markers on the fingerboard to indicate where certain frets are (usually the 3rd, 5th, 7th, 9th, 12th, 15th, and 17th frets).
These are extremely handy and they make it easy for players to know where to put their fingers.
Usually the position markers are dots but other shapes are not uncommon.
For instance, Gibson guitars usually have trapezoids and Paul Reed Smith (PRS) guitars pretty much always come with their signature bird inlays.
Some guitars have very intricate inlay work with vines, flowers, or other shapes!
Sometimes, dot inlays are also found on the side of the fingerboard, looking up towards the player.
The body is the largest part of acoustic guitars and is where the most variation can occur between instruments – just think of all the different-looking guitars you have seen!
Electric guitar bodies can be pretty much any shape, such as Flying V or Telecaster while acoustic guitar bodies tend to always be the classic guitar hourglass shape (although there are different styles of that shape as well!).
The bridge attaches the strings to the guitar body and transfers string vibrations to the body or pickups of the guitar.
The saddle is the part of the bridge which supports the strings.
It is the same as the nut on the headstock in that it determines one end of the string’s vibrating length.
On acoustic guitars the saddle looks very similar to the nut.
Bridge Pins are sometimes found on acoustic guitar saddles.
They are pegs that hold the strings down and keep them attached to the saddle.
Pick guards are a thin piece of material attached to the body located beneath the strings.
They protect the body of the guitar from scratches caused by hitting it with a pick and can provide a nice visual aesthetic to an instrument.
Strap buttons protrude from the body of the guitar near the neck and at the bottom of the body.
You guessed it: they are used to hold and attach a guitar strap to the instrument!
A cutaway is where the guitar body curves in at the bottom of the neck to allow the player to reach the higher frets of their guitar.
Nearly every electric guitar has a cutaway (or two for visual reasons) but it’s also easy to find acoustic models with a cutaway.
Soundboard (Guitar Top)
The soundboard is the top piece of wood (facing the strings) on an acoustic guitar.
It is responsible for vibrating and creating most of the sound when notes are played.
The material of the soundboard is the most important factor for determining an acoustic guitar’s sound.
They are often made from cedar or spruce wood.
The sound hole is the large hole on the body of an acoustic guitar.
This allows vibrations (sound) to escape from inside the body of the guitar and project outwards and also allows the soundboard to vibrate freely.
If you look around enough you may come across guitars with offset soundholes, although most guitars still have them in the center right underneath the strings.
The rosette is the decorative inlaid pattern around the sound hole.
The pattern can be simple or ornate and builders will use them to help brand their different guitar lines.
Rosettes are purely for visual purposes but there are some truly beautiful ones out there!
Upper Bout, Waist, Lower Bout
These terms refer to specific parts of the standard acoustic guitar body.
The waist is the middle of the guitar where it curves inward, the upper bout is the top part closest to the neck which goes outwards, and the lower bout is where the bottom of the guitar goes outwards.
That about does it for the many different parts of guitars!
Underneath somewhat simple exteriors, guitars are made up of many things all with their own purpose, variations, and adjustability.
I hope you enjoy exploring the many varieties of guitars and the individual components which make them up!