A phrase coined by a
single-panel cartoon in the
New Yorker a few years ago. The phrase is the
caption, with a
dog sitting at a
computer with his head turned to talk to another dog. A clever
pun, the phrase soon entered common usage, almost on a par with the "
Information Superhighway," or "
surfing" as a
metaphor for using the
World Wide Web.
Pun though it may be, it should nonetheless be considered in a cautionary sense. On the Internet, nobody knows you're a dog--and you don't know what breed the other dogs are, either. That person you're talking to in a chatroom or exchanging email with could be a nice guy...or he could be a pedophile or would-be stalker. Verification of identities is not easy, and often subject to spoofing.
In the end, although complete paranoia is not usually warranted, caution when dealing with people you do not know is. And if they're sensible, they'll be considering you in exactly the same way.