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Page 1 of 4 What is Streaming?
Until recently the net was confined to text and still images, the level of technology was insufficient to support anything other than the occasional animated gif. Luckily, nothing stands still for long on the Internet and one of the advances this drive for bigger and better technology has developed is 'steaming'. Streaming has become a familiar term for anybody who views moving images on the web, but what it is and how to do it seems shrouded in the mysteries of computer jargon. This article will try to provide a basic understanding of streaming, the major players, and how to go about doing it yourself should you so wish.
To understand how streaming media works, you need to understand the functioning of the World Wide Web. Initially, the Web server takes a request for information, it then pushes that information out as fast as it can, completes the transaction, disconnects, and then continues to carry out other requests from other users. On the client side, your Web browser takes the information it receives, assembles it on the screen, and takes no notice of the Web server until you proceed to click on another link.This is what is called a stateless approach, and it works very well for media like graphics and text. Moving images and sound however, prove more problematic. The time element increases the file size dramatically; (at a rate of 25 frames per second it's easy to see how quickly large files develop, additional storage/extremely large hard drives etc. become essential for any digital video manipulation.) It would be possible to compromise quality somewhat and reduce full motion video down to 12/15 frames per second, but much less than that and it no longer looks like video but a series of still images! Under the stateless approach, the client machine would need to download the entire video clip before it can be viewed. Therefore, the large file size that comes with even short video clips makes the length of time you would have to wait untenable. The aim of streaming media is to bypass these particular limitations. Media data is fed to the user at the same time as the media is viewed. So rather than a stateless data connection, streaming media is more of a continuous connection. The file size of the clip becomes less of an issue when it is spread out over time. The size of the file is still important however. As was discussed earlier, video file sizes can become huge very quickly. 
image with no compression file size: 82K 
same image with compression file size: 4K Compression can be used to get them down to a size that works for a modem or LAN (Local Area Network). The goal of streaming compression is to throw away data that is no longer needed. That process makes the file size much smaller, but also begins to degrade the image and sound quality. One of the challenges of compression is to achieve adequate image/sound quality whilst achieving the smallest possible file size. Next we continue by taking a look at Video Codecs, User Data gram Protocol (UDP), and Transmission Control Protocol (TCP).
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