The unicode character set uses several bytes to represent a character

The unicode character set uses 2 bytes to represent a character. Unicode sets a unified and unique binary encoding for each character in each language to meet the requirements for cross-language and cross-platform text conversion and processing; it can unify all texts in the world using 2 bytes coding.

The operating environment of this tutorial: Windows 7 system, Dell G3 computer.

The unicode character set uses 2 bytes to represent a character.

Unicode (Unicode, Universal Code, Unicode) is a character encoding used on computers. It sets a unified and unique binary encoding for each character in each language to meet the requirements for cross-language and cross-platform text conversion and processing.

If various text encodings are described as dialects from various places, then Unicode is a language developed cooperatively by countries around the world.

In this language environment, there will be no more language encoding conflicts. Content in any language can be displayed on the same screen. This is the biggest benefit of Unicode. It means that all the text in the world is uniformly encoded using 2 bytes. In that way, with unified encoding like this, 2 bytes are enough to accommodate most text in all languages ​​​​in the world.

The scientific name of Unicode is "Universal Multiple-Octet Coded Character Set", referred to as UCS.

The early Unicode standards were called UCS-2 and UCS-4. UCS-2 is encoded with two bytes, and UCS-4 is encoded with 4 bytes. What is currently used is UCS-2, which is a 2-byte encoding, and UCS-4 was developed to prevent 2 bytes from being insufficient in the future.

UCS-4 is divided into 2^7=128 groups according to the highest byte with the highest bit being 0. Each group is divided into 256 planes according to the next highest byte. Each plane is divided into 256 rows according to the third byte, and each row has 256 code points (cells). Plane 0 of group 0 is called BMP (Basic Multilingual Plane). UCS-2 is obtained by removing the first two zero bytes of UCS-4's BMP.

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