Understanding musical notation is a process of understanding the language of sound.
Learning an unfamiliar musical language can be challenging at first, but the more you get used to it, the more adept you will become at communicating through sound.
--- p.10

Fortunately, there is a certain order and rules for the names of sounds.
And there are only seven of them.
Just as a rainbow is made up of seven colors, the names of notes are also made up of seven.
Just as the colors of the rainbow, ‘red, orange, yellow, green, blue, indigo, violet’, have an order, the names of the notes also have an order, ‘do, re, mi, fa, sol, la, ti, do.’
However, the format for calling the name of a sound is different in each country.
For example, you need to remember the sound names of Italian, English, and Korean.
--- p.12

If you look at the piano keyboard, there are no black keys between the notes in the mi-fa and ti-do positions.
In this case, are mi~pa and si~do whole tones or semitones? If we define this distance as a whole tone, we can no longer measure the distance between other notes that require the black keys.
Therefore, the notes mi~fa and si~do right next to each other without a black key are semitones.
In the white keyboard do-re-mi-fa-sol-la-si-do, only the intervals between mi-fa and si-do are semitones.
--- p.53

If we say that a musical score is like a piece of writing, then each musical score has a main character.
Once the main character is decided, the rest of the characters can be decided.
The note corresponding to this main character is called the 'tonic note' in music.
--- p.68

This book is for those who are just starting out in music or learning an instrument but are having trouble with unfamiliar music theory.
For those who want to become familiar with music but have difficulty understanding unfamiliar terms and symbols, we have tried to provide explanations that are as easy as possible.
It explains the basic and fundamental concepts of music in an easy-to-understand way and includes various examples on the piano to show how they are applied in actual sheet music.

---From the author's note