Roku shot themselves in the foot when they originally called apps "channels" to intentionally confuse cable users. They've been trying to recover ever since by constantly changing the name of the Channel Store (the website is still https://channelstore.roku.com). With channels (the so-called live ones) within channels/apps it makes the term "channel" pretty useless.
They've also referred to apps as plugins, which is still better than "channels" and maybe more accurate than apps since the Roku "OS" itself is simply a Linux app. Their documentation generally lags reality, so you'll find old documentation and certainly old threads here using multiple terms for what was originally the "Channel Store".
As for "The Roku Channel", that's an app/channel/plugin like any other, but unlike most apps it has additional premium services available within it. It's also more entrenched than any other app since you can add icons to your Home Screen that take you right to that premium service within "The Roku Channel" (e.g., Paramount+ on The Roku Channel). I don't believe any other app can do this (have multiple icons that actually launch the same app) and it's probably prohibited.
So, "Roku Store" = "Channel Store" = "Streaming Channels" = "Streaming Store" = "whatever they come up with next". Some day they'll probably call it "App Store" as they should have from the beginning and be done with it.
Clear as mud, right? 🙂
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