Streaming - On the Internet, there are two ways to listen to or watch audio and video files. The first way is to download the file to your computer and watch the file after it resides there.
The other way to do it is to start a progressive download of the file, where the file isn't downloaded to your computer in a lasting way. This is called streaming.
For instance, if you listen to a radio station online, you will stream the music, since you're listening live and couldn't download all the songs that they play. Instead, your computer connects to the radio station and receives an ongoing audio feed, or stream, with the radio station's programming delivered to your computer as you need it.
When you stream a file, you will get to listen to or watch it, but won't have the file on your computer to do things with later. Some websites offer streaming as a way to make their content available, but not let people have it without buying it.
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