I don't get why people call this 'Streaming'...
The streaming is when we send over internet the signal, it could be a game, it could be our webcam, or it could be anything else, As example we can see sites like twitch. There we will find tons of real streamers doing their thing. The sites you are sharing in this thread are site to watch movies. I don't think stream is the right way to call them.
It is streaming because you are not downloading the movie but watching it straight from that web site. Its exactly the same thing done by Youtube, Twitch, Netflix, Hulu and the others. Only the content would change. It IS video on demand.
More importantly, it usually uses the old server / client method, rather than the more bandwidth efficient (but less controllable) p2p.
Of course one could argue that downloading a movie you could also start watching it before it finishes and delete it as soon as you finish watching would be almost the same thing.
Streaming does not mean "live". Live content is usually streamed, but it can also be saved so people can download it later. For audio they sometimes call this a "podcast" due to a historical reason (the iPod).
In the end, Streaming means: You start watching/listening before the data "finishes" downloading. For some sources, this data might be endless. Yes, Digital Television is also form of streaming.
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