What is dummy content?
Dummy content — also called placeholder content or filler content — is any text, image or media that stands in for the real thing while a website, an app or a print layout is being designed. It carries no meaning of its own. Its only job is to occupy the same space the final content will occupy, so that everyone looking at the design judges the layout instead of the copy.
The term covers several things that are usually named separately. Dummy text is the classic lorem ipsum paragraph. Dummy images are the grey rectangles with their own dimensions printed across them, or the stock landscapes and round avatars that make a mockup feel closer to finished. Dummy data is the invented names, dates, prices and records that make a table or a dashboard look plausible. All of it is dummy content.
Dummy content is deliberately disposable. It exists to be replaced, and a good placeholder makes its own replacement obvious: nobody ever shipped a page with "Lorem ipsum dolor sit amet" in the headline without someone noticing first.