Do you need internet access to use it and does it use up Data?

Yes and yes

I won the biggest/best Roku two years ago from a radio station. My wife and I can't make sense of paying >$100/month for 15 crappy cable channels, so we use the Roku. Netflix, Hulu, and YouTube get the most use on ours right now. YouTube app is free, but Netflix and Hulu are paid subscriptions (~$10/month each if I remember correctly). We actually just picked up another Roku as my Christmas gift to my wife this year was a TV for our bedroom. This one is actually the cheapest Roku stick and it's powered by a USB port on the TV - huge fan of that as there isn't another power cord running down the wall. Watched the ball drop on New Year's Eve from a YouTube Live stream, and can usually watch college football games no problem.

Best thing we ever did. 7.99 a month and we still don't watch half the channels.

Have ROKU on both of our TVs and love it! We have Spectrum internet and also have a Spectrum TV package that allows us to select something like 20 TV channels from an assortment of 50 or so (once selected it's locked in for a year) for much less $$$ than the standard TV packages (and 200 channels we'll never watch). The wife also buys Netflix & Hulu cards at WalMart so she can have those channels. I watch YouTube for 95% of my viewing, but use Spectrum for weather channel & the occasional look at a reality show (like Alaska, the last frontier or Oak Island), or the local news.

WE have one and use it for youtube, Netflix, Amazon movies, and PBSKids for the littles. The best part is that when they lose or break the remote, any other roku remote will work, and they don't need to be programmed. Just get another one from amazon for 7 bucks and use it.

Well, I got one today at Wally World. Seems like it was worth the $50. I like the fact that I can stream youtube on it. I've been watching a few documentaries on WW1. Seems to be working great so far.