#Ruby

Question

Is this the origin of #hashtag? :-P

Answer 1

The pound sign or hash symbol was often used in information technology to highlight a special meaning. (It should be noted that the words "Pound Sign" in the UK refer specifically to currency "£" - extended ASCII character 156 - and not weight.) In 1970 for example, the number sign was used to denote immediate address mode in the assembly language of the PDP-11 when placed next to a symbol or a number. In 1978, Brian Kernighan and Dennis Ritchie used # in the C programming language for special keywords that had to be processed first by the C preprocessor. Since before the invention of the hashtag, the pound sign has been called the "hash symbol" in some countries outside of North America.

The pound sign appeared and was used by people within IRC networks to label groups and topics. Channels or topics that are available across an entire IRC network are prefixed with a hash symbol # (as opposed to those local to a server, which use an ampersand '&').