1. Alternatively referred to as UCE (Unsolicited Commercial Email) and bulk e-mail, spam, not to be confused with the meat product, is slang commonly used to describe junk e-mail on the Internet. Spam is e-mail sent to thousands and sometimes millions of people without prior approval, promoting a particular product, service or a scam to get other people's money. The first spam e-mail was sent by Gary Thuerk in May 1, 1978 an employee at Digital who was advertising the new DECSYSTEM-2020, 2020T, 2060, AND 2060T on ARPAnet.
In some cases replying to that e-mail indicates that your e-mail address is valid and your e-mail address may be sent to other spam lists, although this is prohibited in many countries. When receiving any e-mail that is clearly spam it is usually best to delete the e-mail. If you think the company is trustworthy or getting spam from a company you shared your e-mail with it is usually safe to click the Unsubscribe or Remove links.
2. When talking in chat, forum, or a newsgroup, spam, also known as flooding, is the process of posting multiple lines of the same text two or more times. In a newsgroup, if a message is posted two or more times, this is also considered spam or a flood of messages.
3. Spam is also a term used in any form of online communication to describe someone who is advertising a product or service.
Also see: Blacklist, Chain mail, Chat terms, Computer crime, E-mail, E-mail bomb, Flood, Graymail, Internet terms, Joe Job, Mail relay, MAPS, Opt, Phishing, RBL, RSS, Scam, Security terms, Spammer, Spim, Spit, Splogs