Today, Comcast and EA announced a partnership in the form of "Xfinity Games powered by EA," a new streaming gaming platform for the cable giant's X1 set-top box, currently installed in 5 million homes according to the latest numbers. The service is aimed specifically at "families that want to play games on the TV and that's casual gamers," Comcast told Polygon.

A well-sourced Reuters report from over a year ago first broke word of an upcoming gaming relationship between Comcast and EA, with the two companies spending a reported two years testing the service. So now, three years into the plan, what exactly is "Xfinity Games powered by EA"? It's a streaming service with games tailored specifically for the platform, coupling the television with players' smartphones or tablets.

Since you probably have a lot of questions, as did we, we're going to share what we know in the form of an explainer.

Is this just EA games?

Sort of. Mostly. The beta service is launching with 23 games, including:

Real Racing 2

EA SPORTS FIFA Soccer 13

MONOPOLY

NBA Jam on Fire Edition

EA SPORTS PGA TOUR Golf

Plants VS. Zombies

Peggle Nights

Word Whomp Underground

World of Goo

"We are launching our beta [today]," EA VP of marketing Katrina Strafford, told us when asked if we should expect games from outside of EA. "It will include 20 games, most of which, but not all, are from EA. We have relationships with publishers across the industry and it's absolutely something we'll explore more as we get feedback from players about what they're liking, what games are really making sense for them in this medium and we'll learn and go from there."

What do the games look like?

Here's an image of Real Racing 2 in action on the X1, using a tablet as a controller.

This functionality appears identical to the way the game works on iOS when paired with an Apple TV using Airplay, a shown in this video:

Is there a marketing video I can watch, of families and friends enjoying Xfinity Games powered by EA on the couch?

Oh, you know there is!

What about EA console games, like Mass Effect or Battlefield?

"We're taking EA's brands and making games and experiences specifically for this new audience that we think we can reach in partnership with Comcast on the X1," Strafford told us. Which means, no, this service isn't for console games.

"These games are made specifically for this platform and for this service. So whereas some of the games we may bring to EA Access are console games that maybe were in development for a year or two, these are games that are made specifically for this platform and not on that kind of cycle. So I think that gives us some of that nimbleness to react to what this new audience is finding most interesting."

So if this isn't EA Access, then how will we pay for the games?

That's not clear just yet. The service launches in beta today, and the games will be available for free. Comcast will gather feedback from users and use that to help determine pricing.

"Comcast's business is built on subscriptions and that can make sense here, but at the same time we have a fantastic on-demand business," Comcast's Bryan Witkowski told us. He added that Comcast will use the feedback gathered during the beta to determine which format works best "before we finalize any pricing decisions ahead of commercial launch."

How does it work?

It uses streaming video, much like OnLive or the PlayStation Now service. Unlike those services, there is no traditional game controller.

Witkowski said, "there's no new hardware required, there's no downloads either on the set-top box or on the mobile device, it's instantaneous, as minimal steps to log in as possible, and there's no physical controllers."

Resolution "varies by game," Witkowski said. "Some of the sports titles are 720p and some of the other casual games are not natively 720p but they still look great on a 55-inch flatscreen television."

Will this count towards my data cap?

Yes, if you have one. "This is all internet content, so it's coming across in the same way as if you use your iPad on your home network it would be internet content," Witkowski said. "We think it's a reasonable amount. So if you live in an area that has any sort of data measurement — we're running some experiments across the country, it's not broadly the case — then that would fall under internet content. "

How do I sign up for the beta?

Easy, you go to http://www.xfinity.com/xfinitygames and hit the Sign Up button. While the beta starts today, users won't all be admitted instantly.

Disclosure: Comcast Ventures is an investor in Vox Media, Polygon's parent company.