Unicode字符集的由来

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Unicode字符集的由来

本文起源于行走在阳光下的那些不可见字符中的知识边界，因为涉及到字符相关，而我也不能很清楚的描述Unicode的前世今生，故而有了此文。

计算机技术的革命极大地方便了人们的工作与生活，使得人类生活前进了一大步，可是在计算机发展进程中，世界各地由于语言文字不一，有过那么一段混乱难受的日子...

字符世界的起源

由于计算机在美国诞生，因此字符集最初也只考虑了美国人当时的需求，诞生了大家熟知的ASCII（American Standard Code for Information Interchange），它由26个基本拉丁字母、阿拉伯数字、英式标点符号和一些控制字符组成。

随着世界的发展，各国人民也开始接触计算机，然而各国人民也有自己独特的文化需求，最开始的字符集满足不了人们日益增长的需求，各国出现了不同的字符集标准，比如国内早期的Java程序员熟知的GBK、GB18030等，我曾经实习的时候接触的用JSP的老系统里就有相关的编码设定，如果用错误编码设定了文档解析格式，可能就会看到乱码，再想想世界上那么多个国家，会有多少编码标准啊，这也是互联网早期乱码比较多的原因吧。

各种编码的字符互不兼容，相互之间的通信可能由于编码的不同，而导致对方看到的是乱码，这就如中国历史中的大秦统一文字和度量单位之前的华夏文明一样，语言不通、货币不通，交流困难。时间的车轮滚滚向前，推动着历史的发展，于是Unicode（Universal Coded Character Set）出现了，它对世界上大部分的文字系统进行了整理、编码，使得计算机能够以更简单的方式来呈现和处理字符，它的目的就是为所有的字符提供统一的编码，任何的平台、系统、设备、应用或者语言都能兼容且无风险使用。

至今Unicode仍在不断的增修，当前最新版本为2019年5月公布的12.1，包含137994个字符，不仅包括当今世界上150种语言模型和历史性的手写码和符号，还包括多种符号集与表情符号。

Unicode

九层之台，起于累土。这样世界性的标准绝不是一蹴而就，必有其坚实的基础，设计原则就是Unicode的一大基础，在《The Unicode Standard Version 6.2 - Core Specification》有提到Unicode的设计原则，

我们熟知的UTF-8其实是Unicode的一种实现方式，即Unicode 转换格式（Unicode Transform Format），是一种为了减少传输数据的大小而设计的变长编码，每个字符使用1/2/3字节按照一定算法进行转换识别。此外，Unicode的实现方式还包括UTF-7、UTF-16、UTF-32、punycode、GB18030等。

总的来说，Unicode于乱世出生逐渐成为标准统一字符世界，至今仍持续发展，造福了社会，极大的提升了生产效率，虽未与ASCII并列与IEEE里程碑，但也是计算机科学史中一件举足轻重的大事记。

本次探索到此结束，全文本着追溯Unicode是什么为什么产生等问题，进行了一系列追寻，大致理清了Unicode的一些“前世今生”，基本对Unicode能够有个大概的认知，需要更加深入的探索的小伙伴可以留言一起探讨~

ps: 及时总结，静心沉淀；如风少年，砥砺前行。

冬至快乐~

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