Does the world really need another video-streaming service?

Comcast (CMCSA -0.52%), the owner of entertainment giant NBCUniversal, is betting the answer is "yes." The company is hard-launching its Peacock service on Wednesday. Here's what investors and potential consumers need to know about it.

Both NBC and Universal are long-established brands in the TV and film spheres, respectively, so the streaming service will have loads of content. Comcast's making more than 600 movies and 400 TV series available on Peacock to start, including a range of offerings in niches such as classic films, current TV series, children's programming, and professional sports. It will be viewable on mobile devices and connected TVs.

Scene from NBC TV drama Chicago Fire.

Image source: NBC (Comcast).

The service has three tiers. Peacock Free viewers can access 7,500 hours of programming, although they will be subject to commercials. Peacock Premium offers 20,000 hours of content and costs $4.99 a month with commercials or $9.99 without.

Existing customers of Comcast's Xfinity Flex and X1 services who have Xfinity Internet or Digital Starter TV (or the equivalent) can get the ad-supported Peacock Premium service for free. 

"We have one of the most enviable collections of media brands and the strongest ad sales track record in the business," Comcast wrote in the January announcement introducing Peacock. "Capitalizing on these key strengths, we are taking a unique approach to streaming that brings value to customers, advertisers and shareholders."

The company is not providing an estimate as to how much revenue it expects to draw from the service. It had said it's aiming for 30 million to 35 million active subscriber accounts by 2024.

Comcast shares closed Tuesday trading up by 1.6%, essentially in line with the gains of the broader stock market and numerous other consumer goods companies.