Final answer:
Adobe Dreamweaver has built-in media playback functionality that enables the preview of SWF or FLV files within the software, using Flash Player to play multimedia content.
Step-by-step explanation:
The feature that allows the preview of SWF or FLV files directly in a Dreamweaver document is the built-in media playback functionality that Adobe Dreamweaver offers. When you insert an SWF or FLV file into a Dreamweaver page, Dreamweaver automatically creates the necessary code that calls on Adobe's Flash Player to load and play the content within the page itself. This is particularly useful for web designers and developers who need to integrate multimedia content into their websites and want to test functionality without leaving the Dreamweaver interface. In Adobe Dreamweaver, the Live View feature allows the preview of SWF (Shockwave Flash) or FLV (Flash Video) files directly within a Dreamweaver document. Live View enables designers and developers to visualize how their web pages will appear and function in a browser without leaving the Dreamweaver environment. When working with SWF or FLV files, Live View actively renders the content, providing a dynamic preview within the Dreamweaver interface. This feature is particularly useful for assessing the layout, interactivity, and overall integration of Flash-based elements, contributing to a more seamless and efficient web development workflow.