Codepoints and notation
A codepoint like U+20B9 identifies the Indian Rupee sign ₹. The U+ prefix signals hexadecimal, so U+0041 is 65 in decimal — the letter A. Characters above U+FFFF, such as most emoji, sit in the supplementary planes and are stored as surrogate pairs in JavaScript, which is why one emoji can count as two UTF-16 code units.