If there’s a gamer in your household, you’ve likely heard of “Fortnite,” the multiplayer phenomenon that’s taken over the world — and the news cycle.

The game burst onto the scene in late 2017 and is now one of the most successful video games ever. Here’s what you need to know:

What is “Fortnite” and where did it come from?

“Fortnite” was published by North Carolina-based studio Epic Games and released in “early access” form last summer. That means it’s technically still in development, even though you can purchase it now for $59.99. The game is what’s known as an open-world survival game, in which players collect resources, make tools and weapons, and try to stay alive as long as possible.

The game is set on modern-day Earth, but most of humanity has disappeared. One of the game’s core mechanics is collecting materials to build protective fortifications.

A few months after its initial launch, Epic Games dropped “Fortnite Battle Royale,” a free mode using assets and gameplay elements from the main game in which 100 people square off against each other in a fight for survival — with the last living player crowned the winner.

This is when “Fortnite” really started to take off — 10 million peoplewere playing within weeks of its release. The battle royale mode is what remains incredibly popular and what most people are talking about when they talk about “Fortnite.”

How big is it?

It’s huge. Epic Games has been quiet about the total number of players, but we know that as of January “Fortnite” had around 45 million active players across all platforms and that number is only going to go up, especially with the recent release of the game on Nintendo’s popular Switch console.

And that still doesn’t even account for the many people who tune in just to watch others play on streaming sites like Twitch and YouTube. There’s something distinctly watchable about this battle royale; its art style, mechanics and fanbase provide endless entertainment, and even celebrities like Drake are getting in on the action.

If “Fortnite” is mostly free, does that mean it’s going to run out of money?

Not anytime soon, that’s for sure. “Fortnite” gets a large chunk of its revenue from microtransactions (small purchases to buy in-game currency) — it’s making over $300 million a month at this point.

Microtransactions are in-game purchases that cost real money in exchange for in-game currency, which can be used to buy various items and skins (slang for how a player looks in the game). Even if a decent portion of players are only chipping in $10 or $20 for some V-Bucks (the game’s currency), that adds up to a lot of money when you consider the player base of the game.

Why has this particular game gotten so big?

“Fortnite” is uniquely welcoming to newcomers, which isn’t true of all online shooter-style games.

Because it’s free, there are always inexperienced players jumping into a match for the first time. Sure, you’re probably not going to top the competition and achieve a No. 1 victory royale on the first try, or even the tenth, but you’re always welcome to keep on trying. You’ll get a chance to observe how experienced players act — when they build, how they stay alive — and have fun along the way, which is really all that matters.

And if it’s not for you, that’s fine too; at least now you have a better understanding of what the fuss is all about.

What does “battle royale” even mean?

Battle royale is a gameplay genre that uses strategy and survival elements in a last-man-standing arena, much like in the Japanese movie of the same name (or, more recently, “The Hunger Games”). It was popularized by the PC/Xbox One game “PlayerUnknown’s Battlegrounds,” which came out earlier in 2017, and “Fortnite” built on that existing formula while adding some new tricks of its own.

In “Fortnite,” battle royale means up to 100 players on a single map trying to be the last person or squad standing as the safe zones get smaller and smaller, forcing all remaining players together. It uses the building mechanics of the core game, so players can create platforms and walls to either get a better vantage point or hide from enemy fire. These structures aren’t impenetrable — you can’t just build four walls and a roof and call it a day.

“Fortnite” is played entirely online with real people, not bots, so every match might be a little different. This is part of the reason for its staying power, despite having only one map. This also allows the developers to make frequent changes and additions, with new “seasons” bringing new story elements and changes.

Is “Fortnite” OK for kids to play?

“Fortnite” is rated T for Teen by the Entertainment Software Rating Board, meaning it’s generally appropriate for ages 13 and up. Some callouts from the ESRB websiteinclude “players use guns, swords, and grenades to fight skeleton-like monsters (husks) in ranged and melee-style combat” and “Battles are highlighted by frequent gunfire, explosions, and cries of pain”—about what you’d expect from a PG-13 action flick.

That rating comes with a huge caveat, though, because online interactions are not rated by the ESRB, and “Fortnite Battle Royale” is entirely online. Obviously, only you can decide what games are best for your children, but you should definitely be aware of what they’re playing and with whom, just like with any other online behavior.

I think I want to give this “Fortnite” thing a shot. Where can I get it?

Because of its massive popularity, Epic Games is bringing “Fortnite” to as many platforms as possible. It’s available to download on PC and Mac, as well as all current-generation home video game consoles.

The Nintendo Switch version launched earlier this month, and it even has cross-play with Xbox One, a rarity. Sony’s PlayStation 4, meanwhile, refuses to join the cross-play party, but you can still play “Fortnite” with your buddies who have that system. That means you can play on your Xbox One using the TV alongside your significant other while they’re curled up with the Switch.

You can even download a mobile version on iOS, with the Android counterpart due out later this year. And, again, it’s free to jump into the battle royale, so why not give it a shot and see what all the hype is about? Good luck, and may the odds be ever in your favor.