what is the difference between ‘normal’ and ‘legacy’ castling?

Normal is dragging the king two square to the side you're castling on or click move to the destination square. Legacy also allows dragging the king to the rook to castle (this still works in 960 in Normal as well I believe)

Actually, dragging the king to the rook works in both. Legacy mode castling also works when clicking the king and then clicking the rook

i dont get it

It's no big deal. Shall we move on, please?

here's the answer guys ( It was soo easy to find!)

i still dont get it

It's just different way to castle in the interface.

ok i guess 😒

I recently read this book. Overall, it was very good, but Chapter 25 was difficult for me. Could someone please explain it to me?

"Study of castling: Advanced theory of castling (chess study series) "

https://www.amazon.com/dp/B0FP4WYC7X/

finallly ty