by Larisa Thomason,
Senior Web Analyst,
Like any useful tool, pop-up windows can be used for both good and evil purposes. For most visitors, a pop-up is either a helpful reminder or a minor annoyance that gets closed as soon as possible. But for visitors with disabilities who are using various assistive technologies, a pop-up window can be quite a barrier to accessibility.
Using Pop-Up Windows
If you spend much time using the Internet, you could probably talk for days about the evils of pop-up windows. Have you run into any of these villains lately?
- Persistent: continually reopens each time you try to close it.
- Pushy: plants itself on top of all other browser windows until you manually close it.
- Sneaky: hides beneath your main window and assaults you when you least expect it. These are often called "pop-under" windows.
- Insolent: spawns a new window each time you try to close it.
- Chatty: a window with sound - usually used by adult sites. Invites you over with a sultry invitation. Just what you need to be listening to when your boss walks in.
Legitimate pop-ups are much more benign.
You can use a pop-up window to display your site's table of contents and keep the window always on top and available to visitors. Ecommerce sites use pop-ups to alert visitors to special sales or free shipping offers. Not all pop-ups are annoying: some actually contain useful information about a site.
Whether they contain useful site information or unrelated advertising, pop-ups often reduce the overall accessibility of Web sites that use them. Here are the major issues you need to consider:
- Site usability: Closing the pop-up or navigating between two open windows may be difficult for someone who has problems with mobility or motor skills. If your site is hard to use, those visitors are apt to just leave.
- Lost on the Web: When visitors click on a link to your site, they expect to see (or hear) a page from your site. If a pop-up opens instead and they hear something unrelated to your site's expected topic, they may think they've arrived at the wrong place and leave.
- General confusion: The BACK button doesn't work in a pop-up window - if it's there at all! Some pop-ups are customized to be a certain size, placed in a certain location, or have the browser's toolbar or scrollbars bar disabled. That's non-standard behavior for most browser windows so some visitors may get confused.
Rules For Accessibility
These problems don't prevent you from using pop-ups on your site, but you need to be aware of the accessibility problems they present and take steps to minimize them.
- Warn users: Always alert users if your link opens a new browser window. For image links, use the ALT text description. With text links, you can use the link's TITLE attribute to describe the link. Both methods increase accessibility and help you include tasty content and keywords for search engine spiders.
- Alternate navigation: Avoid using pop-up boxes as the only navigation option - as with a Table of Contents box. Yes, it is pretty cool to have a little window that controls the big window, but it can be really confusing for someone using a screen reader. Accessible navigation systems always give users alternate, device-independent navigation options.
- Put content in pop-ups: pop-ups that are used for advertising often contain no text content - just images and a link or two. Visitors who can't see the box may mistakenly believe that they've arrived at a page with no content. (Note: that's how search engine spiders feel about most splash pages!) So if your pop-up advertises free shipping, make sure you say it with text, not just an eye-catching graphic.
We also recommend avoiding windows that can't be closed or that spawn other windows with the onUnload event. These confuse and frustrate visitors with disabilities and enrage everyone else.
Use Pop-ups Carefully
Many do this in desperation because pop-up windows are stalking them wherever they go on the Web - and most people don't realize that they are partly to blame. Often, they've downloaded some free utility or music-sharing program that contains a scumware program that tracks your movements online, steals your personal information, and makes your online life miserable by continually harassing you with pop-up advertising! Learn more about scumware and how to thwart it at the ScumWare.com web site.
As with so many other design issues, whether or not you use pop-up windows extensively on your own site depends on your audience. Understand the pitfalls before you spend a lot of time designing and coding them.
Use pop-up windows wisely to make sure they're adding value without compromising either site usability or accessibility.