Jason Munkel and his father Bill are 39 years apart in age, but since last year, they've been sitting down together to play Call of Duty: Ghosts almost every night.
They also broadcast their gameplay to more than 120,000 followers, who watch the father-son duo pursue and shoot enemies on the screen, and talk to them during the game. Sometimes they do this for six to seven hours a day, and their audience has grown dramatically in just one year, though not all watch every day.
It's not just the Munkels; the site where they stream their games has grown to attract millions of monthly viewers, though the duo does have a unique take on streaming.
"A lot of people heard that these guys talk to you, they make you feel like you're part of the family," Bill Munkel, 57, says. "That's what it feels like: We have a big family."
"We're very competitive, trying to win, but still looking at the chat," his 18-year-old son Jason adds. "Sometimes as I'm looking to kill, I end up dying because I'm paying so much attention to the chat, but you know what, I think it's worth it in the end because people respect that, that we do actually care about the people watching."
Bill started playing Call of Duty several years ago, after watching Jason pick off enemies with a sniper rifle in the game, impressed by how good Jason is. Eventually he took up Jason's offer to teach him how to play. Then he went on to play live matches with his son. After a year of broadcasting their games, Bill now says "streaming is in our blood."
"It's almost like a little kid learning a bicycle," he says. "It felt like I got on a bicycle and I took off, and I never looked back."
The Munkels stream their games on a site called Twitch, which has also grown in the 2 1/2 years since it was founded. The site now attracts more than 45 million viewers worldwide every month, with more than a million people streaming their games. The Twitch 2013 report notes that the average viewer is 21 years old and watches 106 minutes per day. A recent graph of the peak Internet traffic in the U.S. puts Twitch ahead of Hulu, Valve and Amazon, behind just Netflix, Google and Apple.
Lionsgate Films recently partnered with Twitch and Major League Gaming to sponsor a StarCraft II tournament to promote the DVD and home video release of the film Ender's Game the first time a Hollywood studio has sponsored a gaming contest. Some say the video game industry is worth more than movie box office revenue.
A lot of people are watching other people play video games online, but why?
Emmett Shear, one of the founders of Twitch, says there are basically two things that draw people to the site. One is that people want to learn from and marvel at the best gamers in the world.
"It's compelling to watch anyone at the pinnacle of human achievement," Shear says. "I think the analogy to understand it is basically like sports: I love playing basketball; it doesn't mean I don't enjoy watching the NBA."
But the other is the same reason that gamers will hang out with each other in the living room and pass a controller around, Shear says.
"[Twitch] can be a stadium, or it can be a living room," he says. "We sort of brought that living room experience to the Internet."
Shear compares it to TV, only the difference is that the people on the screen will talk back to you. Jason Munkel of the father-son duo says talking to the people watching matters more to him than the game.
"It wasn't so much, 'You come in and watch us play.' It was, 'You come in, you hang out, you relax, you talk to the other people, you talk to us, we talk back to you,' " he says. "We have fans that hate Call of Duty. They hate it, they don't even play it ... but they'll watch because of the streamer, not so much the gameplay."
And some of their streamers are loyal fans. Munkel and his father recently got a P.O. box, and they've been receiving fan mail and gifts. For instance, they sing a song every time they get five new subscribers; one of their viewers thought the song could be better, and sent them cymbals and bongo drums.
The Munkels make money by getting a cut of the advertising revenue, and what viewers pay to become subscribers, usually $5 a month. Subscribers can sometimes talk to everyone watching the stream instead of just typing in messages, and they get a newsletter and badge next to their name in the chat room.
What surprised Shear and the team at Twitch is that people don't become subscribers to get rid of ads.
"It's like buying a backstage pass to a concert or a VIP ticket," he says. "Like buying a jersey for your favorite team, it shows your support."
Shear says more than 100 people have quit their jobs to be full-time broadcasters for Twitch. As the site grows, it's also given a boost to games and gaming tournaments, according to Chris Sigaty, production director at Blizzard Entertainment, maker of StarCraft II. He says the first StarCraft captured a Korean audience, but the advent of streaming sites like Twitch has "completely globalized the view of StarCraft II."
Sigaty says the partnership with Lionsgate for the release of Ender's Game was exciting because it wasn't driven by Blizzard, but it also makes sense, given that Ender's Game is about a boy commanding troops to fight bug-like aliens, and StarCraft II lets the player command troops of three races, including a race of bug-like aliens.
But beyond that, game streaming could also give movie studios a boost, particularly those marketing movies for young male viewers, says Anne Parducci, executive vice president for marketing at Lionsgate.
"I feel like this tournament, and the press attention we've been getting, is opening the eyes of probably many studio executives," she says. "This channel is a great way of reaching that younger male audience."
"[Young male viewers are] not necessarily watching broadcast television in the way that other demographics [are]. Gaming is becoming such a popular activity that it makes sense that you would want to reach them there," she says. "I see it personally in that I have two teenage sons, who play a lot of these games like League of Legends, who are familiar with Twitch and Major League Gaming, which was something that was frankly new to me just a short while ago. So Mom became very cool."