What is UTF-8?
UTF-8 is a variable-width encoding of Unicode that uses 1 to 4 bytes per character. ASCII characters take exactly 1 byte (making UTF-8 backward-compatible with ASCII), while less common characters take more, which is why UTF-8 is the dominant encoding on the web — compact for English text, complete for every language.
Example
"A" = 1 byte (0x41); "€" = 3 bytes (0xE2 0x82 0xAC).
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