Internet Streaming: What It Is and How It Works

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What to Know:

  • Streaming is a way to see or hear content without having to download it.
  • Streaming requirements differ based on the type of media streamed.
  • Buffering issues can cause problems for all types of streaming.

What is Streaming?

Streaming is a technology used to deliver content to computers and mobile devices over the internet without having to download it.

Streaming transmits data—usually audio and video but, increasingly, other kinds as well—as a continuous flow, which allows the recipients to watch or listen almost immediately without having to wait for a download to complete.

Overall, streaming is the quickest means of accessing internet-based content. When you stream something, you can start using the content before the entire file downloads. Play a song on Apple Music or Spotify, for instance, and you can click Play to start listening almost immediately. You don't have to wait for the song to download before the music starts. This is one of the major advantages of streaming: It delivers data to you as you need it. 

Progressive download is another option that was around for years before streaming was possible. The key differences between the two are when you can start watching and what happens to the content after you view it. A progressive download requires the entire file to be downloaded prior to watching or listening to it, and the file remains on your computer after you are done with it.

A primary difference between streaming and downloads is what happens to the data after you use it. For downloads, the item stays on your device until you delete it. For streams, your device automatically deletes the data after you use it. A song you stream from Spotify isn't saved to your computer (unless you save it for offline listening, which is a kind of download).

Illustration of movies and popcorn to show streaming on various devices
Patcharapon Pachasirisakun/Getty Images

Requirements for Streaming Content

Streaming requires a relatively fast internet connection; just how fast depends on the type of media you are streaming.

Although each streaming service can be a little different in terms of requirements, safe bets for services like Hulu, YouTube, and Netflix are 2-3Mbps for SD, 5-6Mbps for HD, and 13-25Mbps for UHD and 4K content.

Keep in mind, if others are on your network (family members watching their own videos), it could affect what you are trying to watch.

Live Streaming

Live streaming is the same as the streaming discussed above, but it's specifically used for internet content delivered in real-time as it happens. Live streaming is popular with live television shows, gaming broadcasts, and special one-time events or sports.

Roku TV, Box, and Streaming Stick Examples
Roku TV, Box, and Streaming Stick Examples. TCL and Roku

Streaming Games and Apps

Streaming has traditionally delivered audio and video, but Apple has recently implemented technology that allows streaming to work with games and apps, too.

This technique, called on-demand resources, structures games and apps to include a core set of functions when the user first downloads them and then streams new content as the user needs it. For example, a game might include its first four levels in the initial download and then automatically download levels five and six when you start playing level four.

This approach is useful because it means downloads are quicker and use less data, which is especially important if you have a data limit on your phone plan. It also means that apps take up less space on the device they're installed on.

Problems With Streaming

Because streaming delivers data as you need it, slow or interrupted internet connections can cause problems. For example, if you have streamed only the first 30 seconds of a song, and your internet connection drops before any more of the song has loaded on your device, the song stops playing.

The most common streaming error that crops up has to do with buffering. The buffer is a program's temporary memory that stores the streamed content. The buffer is always filling up with the content you need next. For example, if you watch a movie, the buffer stores the next few minutes of video while you're watching the current content. If your internet connection is slow, the buffer won't fill up quickly enough, and the stream either stops or the quality of the audio or video decreases to compensate.