Highslide JS is an open source JavaScript software, offering a Web 2.0 approach to popup windows. It streamlines the use of thumbnail images and HTML popups on web pages. The library offers these features and advantages:

• No plugins like Flash or Java required.
• Popup blockers are no problem. The content expands within the active browser window.
• Single click. After opening the image or HTML popup, the user can scroll further down or leave the page without closing it.
• Compatibility and safe fallback. If the user has disabled JavaScript or the JavaScript fails in any way, the browser redirects directly to the image itself or to a fallback HTML page. This fallback is able to cope with most exceptions and incompatibilities.

Looks pretty good to me.
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