Learn in the textbookEncoding and Character Codes
DefinitionUnicode is a character code that gives each character of many of the world's languages its own number so that all of them can be handled in one system.
ExplanationThe method that turns the numbers assigned to characters into actual byte sequences is called an encoding scheme (符号化方式); examples are UTF-8 and UTF-16. UTF-8 is a variable-length scheme that uses 1 byte for alphanumerics and 3 bytes for most Japanese characters, and it is widely used on web pages.
AnalogyIt is like a library that catalogs books from every country under one running number. Any book can be found by its number in the same register.
Memory hookUni means one, as in uniform and unit: one system for the world's characters.