RM extension means “Real Media.” It is basically used by the Real Player software. This software streams videos over the Internet which the visitors can watch directly. The files with this extension are often utilized at the same time along with RealAudio and RealVideo files. You can download the Real Media video in RM format for viewing them later. You will need a file called “Real Alternative Codec Pack” which allows different video players to utilize RM. RM can be utilized for listening to music on some of the music players as well. This format is owned by a company called RealNetworks Inc. It also lets users watch different videos streaming on the Internet.
The SWF extension is used by the media files that need Adobe Flash plug-in to play. These files are used by many applications like video embedding ones to total websites. They can create a rich visual experience. The files are normally embedded or included when the site loads and it is not necessary for most users to download them individually. They are also referred to as Flash ones. The company that owned the extension (Macromedia) called it SWF meaning “ShortWave Flash”, but later changed it to “Small Web Format”. Flash files are used by many sites for many different reasons. Some sites use it to add the visual appeal. Most of the users of the Internet have Flash installed. It is one of the most used Internet technologies.
As compared to RM, Flash is a more popular method for adding animation and interactivity to web pages. It is also more commonly used for creating advertisements, animation and other web page components and developing the Internet applications.