Doing stuff on the Internet usually means downloading files. For example, when you visit a Web page, files containing all the text and pictures on that Web page are first downloaded to your computer, and then your Web-browser program opens them. Likewise, if someone e-mails you a picture or a document with yucky work stuff, your e-mail program actually downloads a file before you open it.
Downloading files takes time, especially if they’re big video files. You sit there and you wait. And wait. And wait. Finally the movie file is done downloading and starts to play, but by then you’ve left the room for a cup of coffee again. But software designers are crafty folk, and they’ve devised methods of getting around the problem of waiting a long time for downloads. They’ve come up with two basic solutions:
- Streaming media: Rather than downloading a file to your hard drive, streaming files can be played as the data streams through your modem. It works kind of like a radio, where “data” streams through in the form of radio waves, and that data is immediately played through the radio’s speakers as it is received. With streaming audio or video, no file is ever saved on your hard drive. To truly stream your movies to other people, your movie files need to be on a special streaming server on the Web. There is a remote possibility that your Internet service provider offers a streaming media server, but most service providers do not.
- Progressive download: Newer video-player programs can “fake” streaming pretty effectively. Rather than receiving a movie signal broadcast over the Internet like a radio wave, viewers simply click a link to open the movie as if they were downloading the file. In fact, they are downloading the file — but as soon as enough of the file has been received, the player program can start to play. The program doesn’t need to wait for the whole file to download before it starts. Current versions of QuickTime, RealPlayer, and Windows Media Player all support progressive download. The really cool thing about progressive download is that you don’t need any special kind of server to host the files. Just upload the video file to any server that has enough room to fit it in.
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