Back when the Xbox 360 first launched, gamers everywhere were introduced to "Achievements." These tiny virtual challenges were completely optional, and there was no real reward for managing to complete one ... and yet, it quickly became one of the major reasons why gamers fell in love with the Xbox 360.

It changed the way that people played games: it wasn't just about completing a game anymore, it was about completing a game and finishing all of the Achievements. Gamers pride themselves on "acing" a game, even if there's never been a reward for doing so. It created an entire sub-genre of fans, ones who would play a game for years on end just to grab that last, ridiculously difficult Achievement.

Now, 10 years after the launch of the Xbox 360, Achievements have reached a milestone of their own: there are now more than 100,000 Achievements across all of Microsoft's different platforms. Not only that, but 2015 is looking to be the biggest year for Achievements ever.

According to TrueAchievements, there are now 100,000 Achievements spanning a whopping 3,100 games. That includes everything from the Xbox 360 (where the vast majority of Achievements have been earned) to Windows 8 and everything in between. It all adds up to a total Gamerscore of 2.3 million points — which, at the rate in which games are released, will probably never be reached.

Of course, the folks over at TrueAchievements didn't just stop at the number of Achievements: they've detailed everything from the percentage of Achievements earned through DLC to unobtainable Achievements to Achievements earned by genre.

So, what's the most popular Achievement ever unlocked? According to TrueAchievements, these are the top five:

Alright, it's a little sad that Hexic HD (a game you can't even buy anymore) takes up two of the top spots — but, considering it was bundled with the Xbox 360 at launch, it's not all that surprising, either.

Judging from TrueAchievement's numbers, Achievements are set to become even more popular than they already are: the site's calculations suggest that 2015 will introduce nearly 17,000 Achievements — nearly 2,000 more than the previous record, set in 2011.

You know what that means: time to hit the couch and start a marathon; those Achievements won't unlock themselves! If you'd like to absolutely everything on Achievements and their recent milestone, just head on over to TrueAchievements.org.

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