An Introduction to Basic Music Theory That Every Guitarist Must Know

basic music theory
Written by Glen from

There are plenty of online resources that go into great detail when explaining music theory. However, I find that most of these resources are overly complex and packed full of unnecessary jargon. My goal with this article is to use plain English to describe the basic music theory that every guitarist needs to know.

Don’t get me wrong, an in-depth knowledge of music theory is incredibly useful for intermediate and advanced guitar players. It’s the key to creativity, variety, and purposeful expression. It’s the tool you’ll need to jump from an average player to an experienced musician. In my opinion it also must be earned. The natural flow of an experienced musician comes from hours of work and practice. For the beginner, a simple foundational knowledge is all that is needed.

Many experienced guitar players forget what it was like learning guitar. They forget the awkward, slow-moving fingers. The amount of concentration required to coordinate your strumming with the chord changes. The effort required to remember each chord fingering. Add in music theory and the result can feel like your pulling teeth rather than learning an instrument. No wonder so many give up within the first 6 months!

I want to keep things simple. I want to give you the bare necessities of music. Enough that you can have a simple understanding of how songs work and why things are structured the way they are. This is going to be as painless (and hopefully as useful) as possible. Let’s get started.

Notes and Chords of Basic Music Theory

You’ve probably heard of the basic notes. There are 7 of them: A-B-C-D-E-F-G. Adding in the sharps/flats – A#-C#-D#-F#-G# – brings the total number to 12 potential notes in total (note that there is no B# or E# notes).  It’s called the chromatic scale and is easy to visualize:

basic music theory



Don’t the flat notes make the total count 17? Nope! G# and Ab is actually the same note. The same goes for the rest of sharps and flats – the same note with a different name.

These notes are the backbone of music. Each chord, each scale, each key is built with the same 12 building blocks.

How does this work with guitar?

Each string is tuned to a different note. You’ve probably come across the common tuning of E-A-D-G-B-E. Each fret represents a step up on the note progression. Move up the first fret on the E string and you’ll have the F note. Move another fret up and you’ll have F# – simple as that. It’s useful to point out that after the 12 fret the cycle repeats (usually signified by double fret markers).

Each chord is constructed of a set pattern of the 12 notes. C major, for example, is played using C-E-G. G minor is G-Bb-D. Note that the first note in the chord is always the same as the name of the chord.

The number of chords is vast and complicated. However, beginners can get away with using two types of chords – major and minor. As you master these chords you can slowly add different chord patterns to your repertoire to increase the variety of your playing.

It will be useful for you to understand that each chord can be constructed using the same pattern on the fret board. Take E major for example. Using the basic E major pattern, an F major can be played simply by moving the pattern one fret up. This of course requires the use of a barre chord to keep all the notes consistent.

Don’t over-complicate things. Chords are just patterns of notes played together. Slowly memorize each pattern and you’ll be well on your way to mastering the guitar.


What are scales? Simply put – they are a set of notes that have a certain tonal quality when played together. Like chords, the number of scales is mind numbing. You can spend hours learning every type of scale. Similar to chords, I recommend just sticking to the basic major and minor scales and pick up new scales as you develop. Here are some examples:

The C-Major scale:


Similarly, the A-Major scale:


For those who are curious, there is a set structure to every scale. They are not chosen at random, but rather follow strict guidelines determined by complicated music theory (which we aren’t going to worry about here).

In the same manner as chords, once you know the major scale pattern on the guitar neck you can move the position to whichever note you desire and out pops a new major scale!

Scales aren’t crucial if you want to learn a few songs to sing by the camp fire. They become useful when you are looking to improvise solos or write your own guitar riffs. If you are just strumming and singing with your guitar you can bypass learning scales for now.

Song Key

The key of the song is going to determine which chords and notes can be played. This is incredibly useful for anyone looking to write their own music or for someone looking to jam with their friends.

For example, if a song is written in the key of B major it will use some combination of the following chords:

B major – C# minor – D# minor – E major – F# major – G# minor – A# diminished

These chords are directly related to the B major scale (B-C#-D#-E-F#-G#-A#) and all the chords in this key make use of these notes only.

Therefore, soloing with the B major scale while your friend plays a chord progression in B major will sound spot on. It, of course, continues to become more complex as you throw in pentatonic scales and modes etc., but this is all you really need to get started.

A helpful hint – if you are struggling to find the key of the song have a look at the first chord. The first chord typically will be in the key of the song (although you may find the occasional exception). Knowing the chords in the key will also be incredibly helpful for working out a song by ear. There are only a limited set of chords that can be used for each given key!

If you are writing a song, pick a key you’d like to write in and learn all the chords within that key. Then build your chord progression using only those chords. You can then use scales in that key to create your guitar riffs – simple.


As I mentioned before, these are only the bare bones of basic music theory. Things will only get more complex from here. Don’t be in a rush to learn everything about music theory when you are first picking up the guitar. It will be a while before you actually need advanced music theory and chances are you’ll have forgotten what you’ve learned by then.

Take your time and learn as you go. I hope you’ve found this useful. Be sure to leave a comment below with any advice you have for your fellow guitar players!


About the Author

Glen has been playing guitar for over 12 years. He believes far too many people want to learn guitar but fail within the first 6 months. He’s on a mission to change that by providing the best advice possible to beginner guitar players. His website,, is aimed at improving the world of music one post at a time.



One thought on “An Introduction to Basic Music Theory That Every Guitarist Must Know”

  1. Good Job of selecting the essential information and making it easy to digest. When I try to explain Music Theory, I keep falling down the “too much detail” rabbit hole.

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