Without the black keys, you'd never be able to tell apart the white keys.
...Visually, at least.
There is a repeating pattern in the black keys. Group of 2, then 3.
D is between the 2.
G and A are between the 3.
Think of F and B as a front and back door.
The note you absolutely must remember is C. It's the most important note of all.
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