说明包含或支持（通常理解为在同一地点而不是由通信链路连接）多个终端的设施等。

Including or supporting more than one terminal(usually understood to beat the same location rather than joined by communications links).

一种传送控制字符，用于指明一个或多个后继的位模式不能正确地解释为系统编码或系统链路协议中的字符。

A transmission control character used to indicate that one or more of the following bit patterns have no correct interpretations as characters in the code or link protocol of the system.