E-mail spam, also known as "bulk e-mail" or "junk e-mail," is a subset of spam that involves nearly identical messages sent to numerous recipients by e-mail.
A common synonym for spam is unsolicited bulk e-mail (UBE).
Definitions of spam usually include the aspects that email is unsolicited and sent in bulk.
"UCE" refers specifically to "unsolicited commercial e-mail."
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