Okay, here's Steedy's Music 101 Primer
, which I wrote and posted several years ago. It's a bit long, but very basic and not difficult to understand. Feel free to use what you can, and leave the rest for later.
MUSIC 101, by Stephen H. Lawson
Music theory is nothing more than understanding the intervals between notes, and the patterns of intervals that make up the music we play. You can make it very complicated or keep it relatively simple. I have to keep it simple! For me, the light bulb came on when I looked at the piano keyboard and realized:
ALL of the notes are included in this picture. They merely repeat themselves in the same pattern as they go higher or lower.
The white keys are called the natural notes. There are seven natural notes. The black keys are called sharps and/or flats. There are five of them inserted between some of the natural notes. That gives a total of twelve notes in half-step intervals.
The white keys are in whole-step intervals, except for the E & F, and the B & C. There are no black keys between E & F, and B & C, so those notes are always only a half-step apart.
What are half-steps and whole-steps? The distance, or interval, between two adjacent notes. NOTE: On the ukulele, one fret equals a half-step and two frets equal a whole step.
Western music is based on the Major scale, and on chords constructed from the Major scale. A scale is simply a specific pattern of notes, played one note at a time, starting on any note and ending on the same note an octave higher or lower. There are usually seven notes in each scale, eight if you count the ending note, which is why it's called an octave. Scales that use half-steps and whole-steps are known as Diatonic Scales. Scales that use only half-steps are known as Chromatic Scales.
Going back to the piano diagram, if we play each white key, starting with 'C' on the left and ending with 'C' on the right, that's a C Major scale. It's a C scale, because it starts and ends on 'C', and it's a Major scale, because of the specific pattern of intervals it uses. It's also a diatonic scale, because it uses half-steps and whole-steps.
Now, pay attention. Every Major scale has the same pattern of intervals, which are
: whole-step, whole-step, half-step, whole-step, whole-step, whole-step, half-step
I like to remember the Major scale as a phone number, which would be 221-2221, with the twos being whole steps and the ones being half steps. This is easy to see in the key of 'C', because the C Major scale uses only the white keys, with no sharps or flats.
It gets a little trickier for Major scales (or keys) other than 'C', because those use sharps and flats (the black keys) to make up the same 221-2221 pattern of intervals, and you have to remember how many, and which sharps or flats, are needed depending on what key you're in, or what note the Major scale starts on. You can see this on the piano keyboard by working out the 'whole-step, whole-step, half-step, whole-step, whole-step, whole-step, half-step' (221-2221) pattern, starting on each different note. Then you can play the same scales on the ukulele. Of course, you need to know the names of the notes on your ukulele fingerboard in order to find them.
The notes of a scale can be numbered from '1' to '8', and the chords we play on the ukulele are built from the notes of the scale. A chord is simply three or more notes from the same scale, played together at the same time. A basic three-note chord is called a Triad, and is built using the first, third, and fifth notes of a scale, also known as the 1, 3, & 5 scale tones. If the notes are from a Major scale, then it's called a Major chord. (If the third note is lowered a half-step, it becomes a minor chord, but I'm sticking to Major scales and chords for simplicity's sake.)
Again, it's easy to see with a 'C' chord using the 1, 3, & 5 notes, which are C, E, & G, because the key of 'C' and the C Major scale uses only natural notes (i.e. white keys) with no sharps or flats. It gets a little trickier to build other chords because you have to use sharps or flats to create the same 1, 3, & 5 intervals. But, a triad is always the 1, 3, & 5 notes of a scale.
Now, the songs we play are made up of chords which are built on the scale of the underlying key they are in. If we think of the chords in a certain key the same way we think of notes in a scale, we can number the chords from one to seven. Chord numbers are usually written with Roman numerals to indicate they are chords rather than notes in a scale. The I chord corresponds to the root or first note of the key a song is in. In the key of C, the I is a C chord. In the key of D, the I is a D chord, etc.
Most popular three-chord songs are based on the I, IV, and V chords. In the key of C, that's the C, F, & G chords. In D, it's the D, G, and A chords. In E, it's the E, A, & B chords. You can count on your fingers to find the I, IV, and V chords in each key, or you can look at the Circle of Fifths which is simply a diagram of the chords in each key, and usually shows the sharps or flats in each key, as well. Very handy!
The I, IV, and V chords are almost always Major chords. The chords in between, the ii, iii, and vi chords are usually minor chords, as indicated by the lower-case Roman numerals. The vii chord is a diminished chord, which is seldom used, so we can ignore it for now. The reason some chords are major and others are minor is due to the 1, 3, & 5 intervals. Depending on which note of the scale that each chord is built on, the interval from 1 to 3 can be a Major 3rd (four half-steps) making it a Major chord, or a minor 3rd (three half-steps) making it a minor chord. Or you could say that a minor chord is just a Major chord with the 3rd lowered a half-step.
Keep in mind the I, IV, and V chords are very strong obvious changes, while the ii, iii, and vi chords are weaker, more subtle changes. If you're trying to figure out the chords in a song, try the I, IV, and V chords first, then try filling in the others. The vi chord is closely related to the I chord and is called the Relative Minor chord. It gets thrown into a lot of songs that use the I, IV, and V.
All the different minor scales and modes, and complicated music theory stuff is merely based on variations of the good old Major scale, so basically that's all there is to it!
Anyway, that's all I've got, and that's as simple as I can make it, based on my own very limited understanding. Hopefully, I haven't confused anyone too badly. I'm gonna stop now before I confuse myself any further!