The origins of Humble Bundle are themselves so humble that it renders wordplay obsolete. Ask John Graham, co-founder and COO of Humble Bundle, his proudest achievement with the company and he won't cite his role in building it up from a room in his parents' house, the frequently staggering sales figures, nor its central role in the rise of indie games.

Instead he says, "If I get hit by a bus on my commute to work tomorrow, I would be thinking about how we've raised $26million for charity. It feels special to be celebrating the awesomeness of humanity."

Humble seems to be written into his DNA.

Perhaps that's down to Humble Bundle's origins in an elementary school library. Graham attended school with Jeffrey and David Rosen (he describes them as "twin brother geniuses"), the latter of which cut his teeth in game development in second grade when he made a choose-your-own-adventure war game using Mac programming tool HyperCard. "It was so intense," says Graham, "even with those black and white graphics. Everybody started playing it. Once the librarians realised what the heck he had made they banned it from the library."

Probably hated by librarians everywhere.

Far from discouraged, David Rosen went on to start his own development company, Wolfire Games, in 2003 and spent high school building homebrew game engines. By the time the Rosen brothers graduated from college in 2008, they were looking to assemble a team to make Wolfire a full-time development studio.

"I loved the idea of being part of a game company and trying to get traction, starting from almost nothing," says Graham.

Like any indie they were always searching for new ways to promote their games, and it was here that Graham felt he might excel. "I found I was paying more attention to the marketing and promotion side of things, and I noticed that limited time game sales tended to do very well. And we wondered, little indies that we were, if we could try and put together our own promotion."

While David Rosen focused on developing (the still-unreleased) Overgrowth, Graham and Jeff Rosen went about their first promotional experiment. They teamed up with Natural Selection 2 developer Unknown Worlds to offer players a limited period where they would receive a significant discount if they pre-ordered both games. They hoped it would catch the attention of online communities.

Word spread, and both developers saw record sales days. "We saw weird things happening, like sales off our own websites were actually increasing," says Graham. "We weren't cannibalising our own sales avenues, we were just adding value everywhere." It was a sure sign that the bundle was encouraging people to buy the games who might not otherwise have been interested.

Graham paid keen attention to other sales experiments in the digital marketplace. When Ron Carmel held a pay-what-you-want anniversary sale for World of Goo, Graham was thrilled to see it take huge sums of money. It was from here that the idea for Humble Bundle was born.

"We started wondering, could we do the bundle thing we had just done, alongside the pay-what-you-want that Ron had just done."

Although the primary intention was to promote Wolfire's own games, along with the other included indie titles, Graham knew from the start that the success of the Humble Bundle depended on putting the consumer first. "We'd seen forces in the gaming industry treat the customer like a criminal," he says, "and we wanted people to feel as awesome as possible while they were interacting with this promotion."

"We'd seen forces in the gaming industry treat the customer like a criminal, and we wanted people to feel as awesome as possible while they were interacting with this promotion.

Say goodbye to your free time.

This meant incorporating features that are now Humble Bundle hallmarks; the promotion supported Mac, Windows, and Linux communities; there was no DRM; customers could decide to give a portion of their chosen price to charity. "The whole thing was an honour system," says Graham. "It was about trust in the consumer."

The first Humble Indie Bundle included World of Goo, Aquaria, Gish, Penumbra: Overture, and Wolfire's own Lugaru HD. Graham and Jeff Rosen would man customer support themselves, working from their respective parents' houses where they were living to save on rent. "We were hoping that maybe we could get $100,000 in sales or something," says Graham.

The Humble Indie Bundle went on sale May 4, 2010. In ten days it made $1.27million.

"Jeff and I were slightly delirious doing all the customer support," says Graham. "We swore we'd leave no customer behind."

It was only when the dust settled that they could take stock of what they'd achieved. "The first question was, 'is this real?'" says Graham. "We had to check the bank account to make sure. Then it was, 'oh my god, yeah, it's real.'"

Rather than dwell on their success, Graham and Rosen wanted to know if lightning could strike twice. Buoyed by sudden market recognition, they organised Humble Indie Bundle 2, which was headlined by Jonathan Blow's Braid. It went on sale in December 2010, and broke $500,000 in its first day, going on to raise $1.8million.

"At that point we thought this thing might be repeatable, let's try and turn it into its own business," says Graham. Humble Bundle was spun off from Wolfire Games, and in April 2011 secured investment from Sequoia Capital. This allowed them to expand the team and put together promotions far more frequently. The last thing Graham wanted was to slow down.

The Humble Bundle team is now 35 strong, and, alongside the main Bundles, it also features promotions for mobiles games, music, and eBooks. Collectively, the Bundles have brought in over $50million.

"We've grown up a bit from the days of Jeff and myself doing everything from our childhood bedrooms in our parents' houses," says Graham, as humble as ever.

The sales and exposure enjoyed by parties included in a Bundle meant that a huge number of indie developers now wanted in. Humble Bundle became something of a banner for the indie movement, putting Graham in the difficult position of curator. On one hand it would be financially savvy to include games that already had a profile. On the other, he had the power to bring lesser-known games to a huge audience.

"I think a good curator always looks for things that are going to have broad appeal," he says carefully. "But then they also provide opportunities for people to discover things that they might not encounter on their own."

The aim is to include one game in every major Bundle that's a must-buy. Which game that is will vary according to opinion. "That's the advantage of a bundle of games," he says. "They're all lifting each other up by broadening the appeal."

Bithell loves a good bundle.

This is why Bundles have seated indie poster boys like Hotline Miami and Mark of the Ninja next to slightly lesser known titles: it's beneficial for all involved.

Mike Bithell's already hugely popular Thomas Was Alone featured in Humble Indie Bundle 8. "I think what Humble Bundle does really comes down is making sure everyone has a chance to buy my game at the price they want to pay," says Bithell. "It's a brilliant way of catching all those people who would never buy Thomas Was Alone for anything above a few pennies."

Bithell estimates that around half of Thomas Was Alone's overall sales have come from Humble Bundles - around 350,000. Petri Purho, whose Crayon Physics Deluxe featured in Humble Indie Bundle 3, estimates that around 75 per cent of his Steam players acquired the game through a Bundle.

That's not to mention the impact it can have on individual sales. Like Graham noticed with Wolfire's very first promotion, Bithell found that Bundle inclusion didn't cannibalise his own sales. "It seems to only be an additive thing," he says. "Which is great."

It's hasn't all been smooth sailing. In November 2012 the Humble THQ Bundle launched, featuring a selection of major titles from the now-defunct publisher. It took over $5million, and was responsible for a brief respite in THQ's financial woes.

In August 2013 there was the Humble Origin Bundle, featuring EA games redeemable from their unpopular Origin service. It took over $7 million, making it the most successful Bundle yet. EA donated its portion of the sales to a number of charities.

Yet some were critical of these promotions, commenting that working with major publishers went against the Humble moniker, especially with the presence of DRM. And some believed that the Origin Bundle was a cynical attempt by EA to build an Origin user-base. It was felt that Humble Bundle had betrayed the indie games that made its reputation.

Graham takes a pragmatic approach. "At the end of the day, we're trying to do things that are awesome for customers, and awesome for content creators, and I think if you look at the numbers, we really did make a lot of people happy."

As for the indie community, he believes Humble Bundle working with major publishers can only be beneficial. "They'll attract customers beyond the existing pocket we had originally. We'll then get to do future Humble Indie Bundles, and that's an opportunity to expose gamers who might just consider themselves mainstream gamers to a ton of awesome indie games.

"I don't like carving hard distinctions," he says. "As long as we're making gamers happy and the people that control the gaming content are happy, then we're doing our jobs, and raising tons of money for charity as we go."

Graham adamantly believes in the company's philosophy of putting the customer first. This is despite piracy of Bundle games being an ongoing issue, an inevitable problem in the absence of DRM.

"I think there's a lot of truth to the fact that things are getting more democratised, and the walls of the walled gardens are crumbling a little bit."

Sony's indie push could give Humble Bundle a home on consoles.

"I think there's a lot of truth to the fact that things are getting more democratised, and the walls of the walled gardens are crumbling a little bit. I think there's a potential reality where the digital distribution platforms in which people participate in the future are not going to be the ones that they're forced into. They're going to participate in the ones they choose to participate in. And we take that very seriously.

"We do believe in treating people well, and empowering them, and trusting them, and I don't think we could ever lose or deviate from that without imploding the whole company."

That's not to say the company won't be trying new things. Humble Bundle was built on experimentation, and, as indie games continue to grow in popularity, Graham is always thinking where that might take them, perhaps even onto consoles.

"Yeah, certainly," he says of the possibility. "What it comes down to is that where there's valuable digital content, Humble Bundle could be useful. One thing you'll find in any eco-system is that it'll only be able to promote so much awesome content at a time. I think there's always an opportunity to celebrate the stuff that might not be on the front page anymore. For me that's more of an opportunity on the console side."

It would be a sure fire way to ensure that Humble Bundle continues to play an important role in the ongoing rise of indie games. "[They've] probably introduced the concept of indie games to a lot of new players," says Petri Purho, referring to the company as an "amplifier" for the movement.

Bithell takes this a little further. "There's a very strange knock-on where there's a certain validity a Humble Bundle gives you. It's a kudos that says this is a real indie game; this is an important indie game, at least from a mainstream perspective. I think there are people who don't play indie games, but they'll always look when a Humble Bundle pops up."

Graham's response is suitably humble.

"I think we've been important in showing that indie games are awesome and deserve more attention than they might otherwise find on their own," he says.

"We're always trying to look forward, but there are those moments where you catch your breath and think, did we ever as two guys watching this first promotion from our childhood bedrooms think we would ever build this thing into something that would raise millions and millions for charity? To be able to say that is really special."

Humble until the end.