Before I go any further, the secret of music is intervals. That will make more sense later.
Western music is based a series of notes from A to G. To confuse you, it’s often discussed as starting at C so is written C D E F G A B then back to C again. The interval between these notes is called a tone. There is also an interval called a semi-tone which is the smallest interval in Western music. It is one key higher or lower on a keyboard or one fret higher or lower on a guitar. To confuse you further there is a semi-tone between C and D, D and E, F and G, G and A, A and B but not between E and F or B and C. This is easier to see on a piano keyboard.
Notes on a keyboard
When the note repeats back at C it is double the frequency of the first C when ascending or half when descending. This interval is called an octave.
When we write music on a stave, each line and the gaps between them represents a note. Every Good Boy Deserves Fudge is often used to remember that the order on the lines (starting at the bottom and working up) is E G B D F and the gaps between them are F A C E. If you need higher or lower octaves you can add extra lines above or below as required. This is also shown in the attached document above.
There are 12 notes in an octave. It’s amazing to think that every song ever written or that will be written is based on only these 12 basic notes, albeit in a number of different octaves.
So in a fundamental way, by describing the notes and how to write them down this post contains every song ever written.
But wait, if you want to use these basic 12 notes to create something musical you need to arrange them into a series of Keys containing 7 notes with a specific pattern…..