SWFObject (originally FlashObject) is an open-source JavaScript library used to embed Adobe Flash content onto Web pages, which is supplied as one small JavaScript file. The library can also detect the installed Adobe Flash Player plug-in in all major web browsers, on all major operating systems (OS), and can redirect the visitor to another webpage or show alternate HTML content if the installed plug-in is not suitable.
The library is independent, although related external libraries often integrate with it, such as SWFAddress for deep linking and SWFFit for dynamic content scaling.
With the multitude of Flash embedding JavaScript libraries, SWFObject has emerged as the most popular being used by over 2,600,000 modern websites as of 2011, including high-profile websites such as Ask.com, Windows.com, Time.com, Skype.com, Discovery.com and YouTube.