User agents are not required to support meta data mechanisms. For those that choose to support meta data, this specification does not define how meta data should be interpreted.

用户代理不需要一定支持元数据机制。对于那些选择支持元数据的用户代理，本规范没有定义元数据应该如何被解读。

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Some user agents support the use of META to refresh the current page after a specified number of seconds, with the option of replacing it by a different URI.

一些用户代理支持META的下列用法：在指定数量的秒数之后用一个不同的URI来刷新当前页面。

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