To some people Pop-ups are a frustrating annoyance that should be outlawed from the Internet, but to other people they are a marketing tool par excellence.
Both groups have a valid point of view and have perfectly good reasons for holding those points of view.
First of all let's just clarify exactly what a Pop-up is as there can be some confusion between the different type of Pop-up that exist today.
The most popular kind of Pop-up is a pop-over. This is a browser window that appears when a certain condition is met, e.g. the closing of another browser window or the clicking of a specific link on a Web site that takes the visitor from one page to another.
The pop-over will usually appear in a window that is smaller than the screen and will appear over the top of any existing browser window that might be open – these windows often do not feature standard window controls, menus and so on. The aim is to capture your attention and to present you with an attractive offer such as a special price or a free report, newsletter subscription or other benefit.
Another popular Pop-up is the pop-under. This works in pretty much the same way as the Pop-up, but instead of appearing on top of the current browser window it appears underneath any open browser window.
Another popular type of Pop-up is the exit Pop-up. This is predominantly used as a last ditch attempt for getting the sale, capturing an e-mail address or for simply asking the visitor why they are leaving the site.
Pop-ups first became common towards the end of the 1990s. Initially, nobody was in the slightest bit bothered about them. You'd visit a site, a window would Pop-up offering a special offer or maybe a subscription to a newsletter. If you were not interested you'd simply close the window that had popped-up and that would be that.
Unfortunately, some people took the concept of Pop-ups to a ridiculous level. It was not uncommon to end up in what some people called "Pop-up hell". This term was often used to describe a scenario where you visited a Web site and a window popped-up. When you closed that new window another window would pop up on your screen. You'd click to close the window and up would pop another window. In some really bad cases multiple windows would pop up so as you closed one window two more windows might appear and as you closed each of those yet more would appear.
Sometimes this situation would become so bad that the only way out of the Pop-up hell was to just switch off your computer and start again.
Because some people decided to abuse the power of Pop-ups it became increasingly common for people to install Pop-up blockers. These small utilities simply look out for Pop-ups (or pop-under's) launching and then prevent the new window from opening. They are usually very effective and have seen the partial demise of standard Pop-ups as an effective marketing tool. This has extended into web browsers themselves as well as tool-bar extensions for browsers. There are not many ways in which to block a significant number of Pop-ups.
The use of Pop-ups to create a Pop-up hell, as described above, is strongly not advised (it’s a sure-fire way to guarantee you lose a visitor for good), but used responsibly they can still be an incredibly effective tool in your collection. The keyword here is ‘responsibly’.