What is Unicode?
Unicode is a character set standard that assigns a unique code point to every character across virtually all of the world's writing systems, plus symbols and emoji — over 149,000 as of recent versions. Unicode itself is just the mapping of characters to numbers; UTF-8, UTF-16, and UTF-32 are the encodings that turn those numbers into bytes.
Example
U+1F600 is the Unicode code point for 😀.
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