RealVideo is a video compression format developed by RealNetworks in the late 1990s. It was designed to enable streaming video over the internet, allowing users to watch videos without needing to download the entire file first. This technology was particularly popular during the early days of online video, as it provided a way to deliver content efficiently. The format supports various resolutions and bitrates, making it adaptable for different internet speeds. While it was widely used in the past, the rise of newer technologies and formats, such as MP4 and HTML5, has led to a decline in its popularity.