OTT (over the top) media providers are accessed over the Internet, such as PlutoTV, Tubi TV, Cheddar, Fubo TV, Magine TV, etc. Some are free and some are pay. Some specialize in certain content. There are hundreds of these services and more everyday.
Nothing makes them different. Netflix and Amazon are considered OTT as well, just much more established.
Look on your Roku, smart TV or smart BlueRay player and you will likely see apps for connection to several OTT channels.
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