The definition of the symbols is specified at the beginning of the book. The yellow triangle means “useful tips about common pitfalls and limitations of the circuit” It’s true that perhaps using it for +5V is unnecessary, I’m considering removing it for that particular case.
The symbol is closest to whatever I’m pointing at. If I say something about the ground wires, the symbol would be next to the GND symbol. That’s why it’s sometimes on the right and sometimes on the left side of the text.
The book is not meant to be followed in increasing order of difficulty, so I don’t think I should remove the warnings after the first few pages. The individual sheets can be detached from the binder to be used independently whenever they’re needed for a particular project.
As I mentioned, I believe it’s really hard to condense that much information about all the possible nuances and combinations about a particular circuit. If I were picky I would have also used a pull-down resistor for the transistor, but I prefer to keep it simple, because it will work as is . The book represents a simple and functional circuit, and the online content will support it with additional information, tips, and the code.
This one in particular is “4: LED Custer”, the basics about LEDs is explained on page “1: LED”. There is a page with the essential formulas at the beginning of the book.
This book is meant to help hobbyists to quickly and easily find a clear and functional schematic for a particular project. I believe there is no other alternative for this and I want to solve this problem with this book (and the online content).
Again, thank you very much for your comments, I really appreciate it.