types

Spam has several definitions, varying by the source.

• Unsolicited bulk e-mail (UBE)—unsolicited e-mail, sent in large quantities.
• Unsolicited commercial e-mail (UCE)—this more restrictive definition is used by regulators whose mandate is to regulate commerce, such as the U.S. Federal Trade Commission.

Spamvertised sites

Many spam e-mails contain URLs to a website or websites. According to a Commtouch report in June 2004, "only five countries are hosting 99.68% of the global spammer websites", of which the foremost is China, hosting 73.58% of all web sites referred to within spam.

Most common products advertised

According to information compiled by Spam-Filter-Review.com, E-mail spam for 2006 can be broken down as follows.

E-Mail Spam by Category

Products	25%
Financial	20%
Adult	19%
Scams	9%
Health	7%
Internet	7%
Leisure	6%
Spiritual	4%
Other	3%

"Pills, porn and poker" sums up the most common products advertised in spam. Others include replica watches.

419 scams

Advance fee fraud

Advance fee fraud spam such as the Nigerian "419" scam may be sent by a single individual from a cyber cafe in a developing country. Organized "spam gangs" operating from Russia or eastern Europe share many features in common with other forms of organized crime, including turf battles and revenge killings.

Phishing

Spam is also a medium for fraudsters to scam users to enter personal information on fake Web sites using e-mail forged to look like it is from a bank or other organization such as PayPal. This is known as phishing. Spear-phishing is targeted phishing, using known information about the recipient, such as making it look like it comes from their employer.