Spam

Spam is unsolicited commercial email, the electronic equivalent of the junk mail that comes through your letterbox.

The commonest types of spam concern:
• prescription drugs, drugs that enlarge or enhance body parts, herbal remedies, or weight-loss drugs
• get-rich-quick schemes
• fi nancial services, e.g. mortgage offers or schemes for reducing debts
• qualifi cations, e.g. university degrees, or professional titles available for purchase
• online gambling
• cut-price or pirated software.

Spam sometimes comes in disguise, with a subject line that reads like a personal message, e.g. “Sorry about yesterday”, a business message, e.g. “Your account renewal now due”, or a non-delivery message.

Spammers often disguise their email in an attempt to evade anti-spam software (see Obfuscated spam).

People send spam because it is profi table. Spammers can send millions of emails in a single campaign at a negligible cost (and if they can hijack other people’s computers to send the mail, the cost is even less). If even one recipient out of ten thousand makes a purchase, the spammer can turn a profi t.

Does spam matter?
• Spam wastes staff time. Users without anti-spam protection have to check which email is spam and then delete it.
• Users can easily overlook or delete important email, confusing it with spam.
• Spam, like hoaxes or email viruses, uses bandwidth and fi lls up databases.
• Some spam offends users. Employers may be held responsible, as they are expected to provide a safe working environment.
• Spammers often use other people’s computers to send spam (see Zombies).

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