# 2.4.3 字符型

Emacs Lisp 中的字符本质上是整型数。换句话说，字符是整型数的另一种表示形式。比如，字符 A 实际上表示整数 65。

编程中偶尔会使用到单个字符，不过使用字符串会更加常见一些。字符串就是若干字符的组合体。

字符串和缓冲区内的字符通常被限制在 0 到 4194303内, 也就是 22 位. 其中 0 到 127 称为 ASCII 码, 余下的称为 非-ASCII 码。字符在表示按键映射时十分有用，除了常规按键，它们也会用来表示一些控制键, 比如 Control， Meta， 以及 Shift 等。

有一些特殊的函数可以为消息生成人类可读的字符文本描述。详情查阅 字符描述.


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