Spam filters (13 products)

[edit] Brief Description

Tools to protect your website and email (blog, wiki, CMS) against spammers

[edit] Wiki description

Contents
What is spam? Is it illegal? Types of spam Some spam examples How to prevent spam Spam filters Events Communities Further reading

What is spam?

Initially spam (sometimes referred to as junk mail) was unsolicited email that advertised scams, commercial products or websites. Presently spam is considered to be any unwanted ad that shows up as result of an user contribution on web applications that allows visitors to add content. The primary targets for spammers are wikis, forums, content management systems, blogs, social networks and guestbooks.

Is it illegal?

Not only that spamming is illegal (at least in some jurisdictions) as it involves invasion of privacy, but often the messages received advertise for illegal goods to an underage audience. Just imagine a 10 years old kid checking his email and finding ads for Viagra, Cialis and under the counter pills or hardcore pornographic images publicizing adult chats.

Types of spam

E-mail spam - today, about 80% of emails received are spam; although it might sound unbelievable, email spam is targeted. Whether you receive messages with adult content, ads for IT products, pills or financial products, somehow spammers think that you're interested
Forum spam
Wiki spam
Instant messaging spam

Some spam examples

This probably looks very familiar to Yahoo! Mail users. The bulk folder is full of unread unsolicited e-mails. Personal e-mail has a huge rate of 80% spam. This means that for every newsletter or e-mail that you receive from somebody you know you'll also get 4 spams.

The classic spam message only contains a few lines of text and a link to the advertised product/website. Most likely you'll be redirected to a different address if you click it

When talking about e-mail spam, it's important to know that messages that contain images help spammers to identify your computer. Images also help spammers avoid keyword blockers

By the way, you should never forward any these messages to your friends, you'll just help spammers make their lists bigger and bigger.

How to prevent spam

There are a few tricks to avoid spam. Try to

never publish your email address or instant messaging ID on public websites. If it's really necessary, try being creative and use stuff like "[at]" or even better " " (space) instead of "@", "dot" or "d0t" instead of "." You can even create a simple image that spiders won't be able to read. I often use
read the TOS when you sign up for a website or install a software product. Look out for anything suspicious like "When signing up for this website's services you agree to be contacted by third parties concerning products you might be interested in"
use two e-mail addresses: one for corresponding your friends and co-workers, and one for everything else
use specialized software to prevent your e-mail inbox, blog or forum from being suffocated with unwanted ads
never respond or forward spam, click links in spam messages or download images in spam emails
keep your login details private
repair the damage that's already been done: use search engines to see if your email address is indexed anywhere and if so, contact the webmaster and kindly ask him to remove it

Spam filters

Spam filters can block spam email, spam comments and wiki vandalism. Most webmasters use CAPTCHAs, but statistics show that sometimes humans get those wrong too. Keyword filtering can be effective, but it's important to update your list frequently. A spammer will never use "Viagra" twice, he'll write "V1agra", "Vi@gra" and "Viiaagra" too. If you're trying to keep a website clean, moderation of all contributions will do the trick, but users might get discouraged by this method and add less content.