Spam is unsolicited bulk messaging that wastes attention and often carries fraud, unwanted offers, or links toward unsafe pages.
It is sent widely with little personal research, which separates it from a lure written for one named person.
How it works
The sender wants volume, whether the channel is mail, comments, or a public form.
Filters look at reputation, repetition, and how fast the messages arrive.
A computational cost on each submission makes huge scripted waves more expensive to run.
People still need a way to report a new wave that slips past the filter.
Concrete examples
- A mailbox fills overnight with copies of the same loan offer.
- A blog receives hundreds of comments that repeat one link.
- A contact form is submitted by a script that never reads the page.
Protective measures
- Score inbound mail with sender reputation and repetition, not only with blocked words.
- Limit how often a public form accepts submissions from one source.
- Give readers a simple report action for messages the filter missed.
- Separate bulk advertising from targeted fraud so each gets the right control.
How CDPCaptcha helps
Proof of work raises the cost of automated bulk posting because each attempt must spend computing time before the site accepts it.
CDPCaptcha is a self-hosted proof of work check in the browser, with no cookies, no tracking, and no picture puzzles.
It is made and hosted in the EU, in Germany, and the service is described at https://cdpcaptcha.com/.
Related articles
What is spear phishing? contrasts a researched message for one person with this unsolicited bulk pattern.
What is web scraping? describes automated collection of pages, another high volume behavior that is not bulk mail.
What is spoofing? explains how a forged sender label helps bulk messages look trusted.