One story says it was first used during the early days of the telephone to tell an operator that a message had been received.

VOA: special.2010.02.28

The situation is especially difficult when your critic is anonymous, as then you first need to persuade a website or message board operator to disclose the person's identity.

FORBES: Magazine Article

And eventually, a telephone operator -- a telegraph operator sent out a simple message to the cheers of a waiting nation.

WHITEHOUSE: President Obama on the National Wireless Initiative

Whether a message gets through depends on what phone the recipient is using, the operator they have signed up with and which part of that company's network they are currently using.

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