What is Spam?

Annoying emails, IMs, texts, voicemails and other digitally distributed messages that you’ve received but never would have asked for? Those can all be described by a single word – spam.

3 min read

3 min read

What is spam?

Spam is any form of unrequested communication sent in bulk. Depending on the content of the message, there are two main types – Unsolicited Bulk Emails (UBE) and Unsolicited Commercial emails (UCE).

If the email or message is unsolicited and deceptive, it is probably spam. One of the most common ways to spread unsolicited content is through botnets – large networks of robots or infected “zombie” devices. Chain letters and hoaxes are also considered to be spam, although these differ in that they are usually passed on by people with good intentions.

Origin of the term

Any fan of the British comedy television show Monty Python probably already knows where the term comes from. In the show's 1970 ‘Spam’ sketch, two guests are ordering a meal in a greasy-spoon café and notice that nearly every dish on the menu contains SPAM® – a type of canned meat . Even though one of them doesn’t want SPAM in her meal, it soon becomes clear the ingredient is almost impossible to avoid – much like the unsolicited email messages.

Different types of spam

If the email, message, or any other form of bulk communication is unsolicited and deceptive, then it probably is spam.

Trojan Horses, similar to the Trojan Horse known from ancient Greco-Roman tales, a Trojan virus hides its true function, often disguises itself as legitimate software, in order to gain unauthorised access to a device. After reaching the targeted machine, it often employs various techniques to be executed by the user or by other software on the affected system.

Zombies are a computers connected to the internet that have been compromised by a hacker, computer virus or trojan horse program. These are then used to perform malicious tasks under remote direction. Botnets of zombie computers are often used to spread e-mail spam and launch denial-of-service attacks (DOS attacks).

Phishing is an email scam in which the criminal impersonates a trustworthy entity to obtain sensitive data from the user.

Scams are fraudulent methods which is used to obtain money or personal details such as a credit card number. Scammers prey on others with deception through the buying and selling of illegitimate goods and services, fake charities, dating websites and threats/extortion.

How to protect yourself from spam?

Ensure you are using a secure email server.

If you must share your email address publicly, edit its format to make it harder for spammers to find. For example, writing it in a different way or sharing it as an image rather than a link.

Last but not least, use a reliable anti-spam solution.

Brief history

The first spam email campaign was observed in 1978, landing messages in the inboxes of nearly 400 (or 15% of all) users connected to the internet’s predecessor, Advanced Research Projects Agency Network (ARPANET). It advertised a company’s product presentation, but after receiving a great deal of negative feedback, this form of marketing was abandoned – at least for a time.

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As the internet grew to global proportions, so did spam. In the years after 2000, its numbers have exploded, reaching a peak around 2008, when global spam accounted for over 90% of all email traffic. Moreover, it didn’t just spread unsolicited ads, but also phishing links and other fraudulent content, as well as dangerous malware families, making it into a serious security threat that desperately needed to be addressed.

The pushback came on multiple fronts. Cybersecurity vendors and software developers created anti-spam solutions – many based on machine learning – capable of filtering this kind of communication. Legislators also came up with anti-spam laws that made sending spam illegal and prosecutable – which has led to legal cases against perpetrators of spam campaigns.

In 2008, McColo, a California-based hosting provider was shut down because it hosted machines responsible for sending “unsolicited commercial email (UCE)” messages. It is estimated that McColo’s servers were accountable for three quarters of all spam messages sent worldwide at that time.

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