This is convention, so on almost-- and most any computer you overuse, if you're writing code that uses a char, you're gonna be handed 8 bits or 1 byte to store that particular char.

这是约定，对于大多数-,电脑，当你写代码要用到一个char型数据时,必须先预留8比特或1字节,的空间来存储这个char型数据。

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