Browser Pop-ups and Pop-unders

Browser Pop-ups and Pop-unders

• Embedded code in web pages pops up annoying ads
• Pop-up blockers are available for most browsers
• Pop-unders get around these by putting ad beneath
• Not usually a threat - just annoying!

The commercialisation of the Internet has led to advertisers grasping the new medium and
employing many new tactics to promote their brands and products as effectively as possible.
The interactive features of HTML and embedded scripting (programming) languages such as
JavaScript have allowed these advertisers to step outside the web page, and create ads that pop
up or overlay the pages they are embedded into.
In itself, there is nothing wrong with this behaviour; the advertiser's revenue often keeps
resources online that would otherwise have to close. However, the ability to pop-up information
can be exploited and overdone, and it is often an intrusion rather than effective advertising.
More malicious websites have also exploited scripts to do more than just pop-up windows; some
can install software or modify your system settings to allow intruders into your computer. There
are safeguards built into the more up to date browsers - they usually warn you if something is
about to be installed, and give you the choice of cancelling.
Attacks through pop-ups are rare, and the main problem with them is the annoyance factor.
Increasingly, browsers have built-in pop-up blockers, or you can download or purchase them
separately (e.g Google's toolbar for Internet Explorer), though the advertisers are finding ways
around this, using pop-unders (they just hide below your browser window, appearing when you
close the page).