I hate to put my ignorance on dispolay for all the world to see but here goes...what's Roku? I subscribe to Netflix directly.
Roku is a streaming device. It's a little box about the size of a hockey puck. It offers a variety of streaming channels, some free, some that require a subscription. It was probably the first streaming apparatus that brought streaming away from computers and laptops and brought it to TVs. Now streaming is built into many Blu-ray players, game systems and TVs. But Roku has the most choices, IMO.
Roku has more choices, and simply works better than my TV or Blu-ray players for streaming, has a better interface, etc.