E-mail tracer used by HP 'extremely common'
October 14, 2006Robert McMillan
The technology tool the company used, called a Web bug, is designed to allow e-mail senders to track the path a message takes, including whether a recipient opens the message and forwards it to another party. And it turns out the technology is widely used in e-mail newsletters to track readers and also by law enforcement in investigations, security experts say.
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