Basically you have servers that have the video you stream, and it goes to each person individually, through fiber optics or whatever, to each persons house (super simplified). If only one person watches, they get 100% of the output, if another person jumps on, it splits, and so on and so on. Radio and TV is completely different. They aren’t connected to anything except the transmitter. They send their signal as a wave into the air, on whatever channel of the EM spectrum they’re allowed. It’s just sent through the air, waiting for the receiver in your tv or car to pick up.
Netflix is like actively taking the video from them, and tv/radio is like passively picking up what they send into the atmosphere.
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