trache

A pop-up is a child of the browser window you are visiting currently. It pops up above your currently website and sets the focus to itself (so that you then have to close it or click another window to interact with something else on your screen).

A pop-under is also a child of the current website and pops up, but then sets the current window back to the website you were viewing. You're guaranteed to at least see this one because you do have to close it to get rid of it. In a sense it is supposed to be "unobtrusive" and you only see it when you are closing a bunch of windows. In my opinion it is still just as annoying.

The difference between pop(ups|unders) and this new wave of advertisements, is that the new adverts use Dynamic HTML... you often see this in the form of advertisements that "float" above the current website but not in their own window. They'll often show up on the left hand side of the screen and move to the right waiting for you to click on a "Close" or "X" link near the advertisement to getr id of it.

In effect this is "completely legal" (in the sense of trying to fight it with a popup blocker) because it's not a pop(up|under) but simply fancy HTML.

I have Firefox 1.0.1 (just released) and the latest version of Adblock with G's filterset (http://www.geocities.com/pierceive/adblock/). I hardly see any advertisements, and it allows you to add and remove images at will (just right click them). If you have an issue and cannot see something you were meant to, you can always toggle Adblock (press CTRL-SHIFT-B) and reload the page. It also blocks Flash files (at your discretion of course).

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