Pitch is the raw material. This chapter is about the names attached to it. There are only seven of them, and the two naming systems you have probably met are pointing at the same keys.
Every pitch has a name. Different places and different situations use different names for it, but they point at the same sound. Start with the keyboard below — pressing a white key plays it.
The white keys are named C, D, E, F, G, A and B. Seven of them, then it starts over at C. There are only seven names, so that part of the memorising is already done.
How Do-Re-Mi maps onto C-D-E
If you learned "Do, Re, Mi, Fa, Sol, La, Ti" at school, those are the notes you just pressed. Same sounds, different labels. Instruments and software almost always print C, D, E, so that is what this series uses. If Do-Re-Mi is what feels natural to you, check the mapping below.
How high or low a note is. Physically it is how fast the air vibrates, but for this series "further right on the keyboard is higher" is all you need.
Why the black keys exist
With only white keys, the gap between neighbours is not the same everywhere — some gaps are twice as wide as others. The black keys sit in the wide gaps and cut them in half. A black key is named after the white key on its left with a sharp (♯) added, or the white key on its right with a flat (♭) added. One key, two names, depending on which side you are looking from.
Why the same name appears more than once
Move eight white keys to the right and you are back at C. Different height, same name — and it genuinely sounds like a version of the same note. That relationship is called an octave. It is why a low voice and a high voice can sing the same song and it is still the same song.
The distance between two notes with the same name — eight white keys apart. Different height, but heard as the same note in a higher or lower register.
Once note names make sense, chord names become readable too. Before the next chapter, generate a melody over C, G, Am, F and watch the note names go by.
Generate a melody on this progressionSeven white keys and the names start over. Do-Re-Mi and C-D-E are the same notes under different labels.