1. Home
  2. Marketing Glossary


What is spam?

The word spam has multiple meanings, such as unwanted email, junk email, unsolicited emails, etc.

In a few words, spam is any type of publicity that we receive in our email inbox and that we have not authorized, that is to say, it is sent from someone that surely we don’t know and that only wants to sell us something.

1. Why do people send spam?

Spam is used because it is lucrative and despite the fact that practically everybody detects it, there are people who read spam messages, so many spammers end up making some money out of this kind of strategy (their goal is to promote products or services).

The origins of spam are as old as those of email itself, although email providers (ESPs) fight so that companies that send spam don’t impact users, the truth is that a percentage of the spam sent is delivered, and can’t be stopped. Spammers look for ways to bypass anti-spam filters with varying degrees of success.

It is important to clarify the difference between spam and phishing: Spammers seek to make sales while hackers who send phishing seek to steal users’ personal data with which to obtain important financial advantages.

2. Antispam filters

Antispam filters take into account a multitude of factors to classify an email as spam. Although it is true that each company can apply rules locally to stop spam, the most common thing is that all of them at least take into account these factors to detect spam:

  • Subject line. A subject line in capital letters, with exclamations, with interrogations, too long or too short, is analyzed more carefully by the antispam filter.
  • DNS settings. The filter will check the DMARC, DKIM and SPF settings to validate the sending domain; the software will have to make sure the message was authorized by the domain administrator.
  • Content. They take into account whether the text contains any terms related to the financial world, adult content, drugs, etc. The use of shorteners also tends to generate distrust in the filters.
  • Design. They check multiple aspects of the design for suspicious parameters, such as images with embedded text, many images and little editable text, email size, etc. Sender domain reputation. The number of messages sent from the same domain and if the sender is in the recipient’s contact list (if it is trusted).

3. I don’t want to send spam

Nobody wants to be considered as a spammer, by this we mean that we don’t want our emails to be sent to the spam folder, neither those who send legitimate mailings, nor spammers. To prevent your emails from landing in the spam folder, you should respect the local regulations, such as the European RGPD or American CAN-SPAM. Some basic good practices you should follow are:

  • The first aspect you should consider is the quality of your mailing lists. Contact lists need maintenance, so if an email is flagged as hard bounced, don’t send to it again, try not to send to contacts that have not shown activity in the last 3-6 months and never use databases offered by third party companies or give your own mailing list to another sender. Only in this way, your sending reputation will remain high and you will avoid the dreaded spam folder.
  • Always with permission. Only send email campaigns to subscribers who wish to receive your communications and who have authorized you to do so. That is to say, you must have the unequivocal permission from your subscribers, so always ask for their consent; double opt-in forms will be essential for keeping the quality of your databases.
  • Allow users to unsubscribe without any problem. So always include an unsubscribe link, it should be visible and easy to find.
  • Include real and visible contact details. A legal text should be included in the mailings so that the recipient can exercise their rights under the RGPD or CAN-SPAM, real contact details of course.