Everyone gets spam (junk email) these days. These spam mails are sent to your email account everyday. It is flooding the internet with many copies of the same message and forcing the message on people who would not otherwise choose to receive it. They are a real nuisance!

Most spam in fact is commercial advertising. The most common items advertised in spam messages are: Pornography site subscriptions, prescription drugs, purported sexual enhancement products, printer ink cartridges, counterfeit brand name goods, counterfeit software, mortgage offers, fake diplomas from nonexistent or non-accredited universities, and pump and dump penny stocks. In fact spam costs the sender very little to send — most of the costs are paid for by the recipient or the carriers rather than by the sender.

Technically, there are two main types of spam, namely Cancellable Usenet spam and Email Spam. Both of these spams have different effects on Internet users. Cancelable Usenet spam is a single message that sent to many Usenet newsgroups while email spam targets individual users with direct mail messages.

The US Department of Energy Computer Incident Advisory Committee (CIAC) has provided specific countermeasures against electronic mail spamming. Some popular methods for filtering and refusing spam include e-mail filtering based on the content of the e-mail, DNS-based blackhole lists (DNSBL), greylisting, spamtraps, enforcing technical requirements, checksumming systems to detect bulk email, and by putting some sort of cost on the sender via a Proof-of-work system or a micropayment. Each method has strengths and weaknesses and each is controversial due to its weaknesses.

The above methods may cost you some money. Be a user, just bear in mind. When you receive these junk mails, what you have to do is just hit the “Delete” key in your email program. Sometime you might see in the spam message that you can remove these mails from their mailing list by just replying to their request. Don’t be fooled. If you reply to a spam message, it just confirms that your address is valid. Your email address will then be sold to other spammers and you will receive more and more spam.