After 10 weeks of open qualifiers attracting more than 40 million competitors, the Fortnite World Cup finals will be held this weekend in New York. Up for grabs for the 100 qualifiers – many of whom are between 12 and 16 years old – is a total prize pot of $30m, the largest ever for an esports event.

With more than 250 million players, Fortnite: Battle Royale has become one of the most popular video games in the world since its launch in 2017. The World Cup represents the title’s entry into the lucrative world of professional games tournament circuits, where revenues are set to pass $1bn this year, due to exploding sponsorship, advertising and broadcast rights.

Epic Games has arranged a three-day festival around the finals, with thousands of fans expected to attend. Saturday will see the Duos final with 50 teams of two competing, while Sunday features the Solo competition, pitching 100 players against each other. Both finals are played over six matches, with points awarded for match placement and number of kills. Winners of the Solo and Duo finals will receive $3m each.

Photograph: Epic Games

Competitors are coming from all over the world after winning a series of open, online heats, which also offered hundreds of thousands of dollars in prize money. There are no women among the finalists, and most competitors are under the age of 20. Many are part of professional gaming teams such as Faze, Envy and NRG, which provide managers and training facilities for star players.

Quick Guide What is Fortnite? Show What is Fortnite: Battle Royale In short, it's a mass online brawl where 100 players leap out of a flying bus on to a small island and then fight until only one is left. Hidden around are weapons and traps, and players must arm themselves while exploring. When was it released? Fortnite started in July 2017 as a four-player cooperative survival game, but the game's developer, Epic, noticed the huge success of PC title PlayerUnknown's Battlegrounds (PUBG), which pits 100 players against each other, and decided to release a new version. How much does it cost? The game is free and players are able to unlock new items as they progress without paying anything. A Premium Battle Pass gives access to exclusive clothing and items. However there is an in-game currency, V-Bucks, which players can use to buy additional custom gear. It is how this currency is paid for that has become the centre of a dispute between Fortnite's makers and Apple and Google. Why is it so popular with kids? It's free, it's fun, and it has a very silly, offbeat sense of humour. While PUBG has a serious, realistic visual style, Fortnite: Battle Royale has very bright, almost cartoon-like graphics, as well as loads of ridiculous items and costumes, such as space suits and dinosaur outfits. Players can pull a variety of dance moves, and team up with a friend to compete as a duo or a squad. Participants can chat as they play using headsets and microphones. Is there violence? And is it addictive? Although Fortnite is a multiplayer shooter, it does not depict bloody violence. It takes lots of enjoyable gameplay concepts from more mature shooting games but places them in a non-threatening, non-realistic world. In terms of addictiveness, Fortnite contains nothing that makes it different from other action video games. It's more that the game contains many different elements – nice visuals, good shooting mechanics, an interesting building component and lots of support and interest from YouTubers – into one package that is free to download. Photograph: fortnite

Several UK competitors will be present, including one of the favourites to win, Benjy “Benjyfishy” David Fish, who is competing in the Solo and Duo competitions for NRG Esports. The 15-year-old told ESPN that if he wins, he will buy a house for his family.

Fortnite: Battle Royale has had unprecedented growth since its release as a free offshoot of coop shooter game, Fortnite: Save the World. In each online match, 100 players are parachuted on to a colourful island and must search for weapons and items while shooting competitors. The last person standing wins.

The battle royale genre was popularised by Player Unknown’s Battlegrounds, released in 2017. Apex Legends attracted 50 million players in a week after its launch in February. Fortnite, meanwhile, has proved enormously popular with younger players thanks to cartoon visuals, amusing dances and high-profile star players who attract millions of spectators on their YouTube and Twitch channels.

Fans can watch the finals live online via Fortnite’s Twitch and YouTube channels from 1pm ET (6pm BST) each night, and can tune in through the game itself, selecting to follow a major broadcast or to view the live streams of individual players.

Industry insiders speculate that Fortnite’s popularity has peaked, with viewership of Twitch streams falling through 2019, and May revenues dropping 38% from 2018. The viewing figures from these finals may provide the most compelling verdict yet on Fortnite’s popularity.