Blocking Pop-ups

 < Day Day Up > 

Pop-ups are ads that are displayed in their own browser windows. There are two classes of pop-up ads: a pop-up, which displays on top of everything and has focus, and a pop-under, which is placed behind the browser, lurking and waiting for you to find it later. The logic behind pop-under ads is that you might not know from which site they originated. In this chapter we'll refer to both as pop-up ads, even though some are pop-unders.

Another related technique is called a pop-over. These ads are displayed using JavaScript and are part of the web page (no separate browser window). Pop-overs are usually animated, covering the content you want to see.

For the longest time, pop-up ads were not blocked by Internet Explorer. Only after third parties started offering pop-up blockers did Microsoft realize that it had to do something. (And, yes, Firefox did figure into that as well!)

Probably the best known pop-up blocker is the Google toolbar for Internet Explorer. This add-on to Internet Explorer has proven immensely popular. My Google toolbar pop-up blocker has blocked about 1,400 ads since it started counting! That is a lot of ads that I don't have to be bothered with.


Adware, spyware, and other malicious software are often used to pop up spurious browser windows, even when the user is not actively on the Web! Usually nothing in the browser is able to block these types of programs, although you might be able to block the sites from which the ads come. This can be done with an extension such as Adblock (covered later in this chapter). The best way to avoid adware and spyware is to not allow these programs on your machine. Be very cautious of websites that offer games, tools, and so on for free. On computers that are not well configured, just visiting a website can cause undesirable software to be installed. However, the most common way to install adware or spyware is to ask and hope the user doesn't realize that adware or spyware is being installed. Firefox allows software to be installed only from sites that have been preapproved, either by Mozilla prior to installing Firefox or by the user. Only install software from companies you know and trust.

Two technologies are used to create pop-up ads. The first, and most easily blocked, is to use HTML to create a new browser window. The other technology is to create a pop-up using something such as JavaScript or Flash. These pop-ups are more difficult to stop because, once started, they do their dirty work without any further interaction with the browser!

Some websites attempt to use pop-ups to interact with the user, such as to get a username and password. This is certainly not the best way to interact with users. I still remember one site where I sat for almost a minute wondering why nothing was happening, only to realize the site had tried to pop up a new window. Microsoft's Exchange Server web interface uses pop-ups, and that requires the user to enable pop-ups for that site.

     < Day Day Up > 

    Firefox and Thunderbird. Beyond Browsing and Email
    Firefox and Thunderbird Garage
    ISBN: 0131870041
    EAN: 2147483647
    Year: 2003
    Pages: 245

    Similar book on Amazon © 2008-2017.
    If you may any questions please contact us: