It may be a little difficult to believe for some, but the PS2s that many gamers grew up playing are now more than two decades old. It's a console that set the tone for an entire generation of systems, and, during its 13 years in production, sold more than 155 million units.

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Since production of the console finally ceased in 2013, it's been gaining popularity as a retro gaming collectible thanks to its excellent library of games. Although the technology inside the little black box is considered "retro" by modern standards though, it was incredibly impressive for its era and offered some unique and interesting functionality that many players weren't aware of.

Updated April 14, 2021, by Thomas Bowen: Despite the countless consoles that have followed it, Sony's PlayStation 2 remains the best selling video game console of all time. Although some of Nintendo's earlier handhelds aren't too far behind, the closest home console is the PS4, which is more than 40 million units behind.

There are numerous reasons for the console's success, although many will point to its excellent library of games. The console itself was also a technical masterpiece though, offering a ridiculous amount of functionality that was years ahead of its time. With that in mind, it seems pretty unlikely that the PS2's sales record is going to be broken anytime soon.

10 It Can Be Used As A Desktop PC

The PS2 was a pretty powerful machine, which is perhaps why Sony offered a special package for those interested in using the console to make their own gamest. This was an incredible step forward in enabling the indie gaming industry, which was pretty much non-existent at the time.

For those who were committed to developing their own titles, it was possible to pick up a package containing a mouse and keyboard, a Linux CD, a network adapter and a hard drive with about 40 GB storage. The latter may seem pretty small by modern standards, but, for the time, it was actually pretty big.

9 Players Can Use Their Bodies As Controllers

Nowadays PS VR allows gamers to play incredibly immersive titles simply by moving their arms and head. Back in the day, however, the closest thing that players had to this, aside from the EyeToy, perhaps, was a third-party device from a company called ThrustMaster.

The so called "Fighting Arena" tracked the arm and leg movements of players and converted them to controller inputs. There was quite a lot of lag and the tracking was often terrible, although it did provide an excellent workout and a fairly unique method of playing video games.

8 It Can Connect To The PSP

Just as the PS Vita can be connected to the PS4 for some extra functionality, its predecessor, the PSP, could be connected to the PS2. Granted, the functionality was nowhere near as extensive as the PS Vita, but it was still pretty revolutionary nonetheless.

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Connecting the PSP to a PS2 provided players with extra content in a few different games and, in some cases, even gave them new powers that weren't included in the full console version. Despite Sony's handheld selling more than 80 million units though, many still weren't aware of this additional connectivity.

7 It Can Connect To Broadband Internet

These days, it's something of a given that a video game console will be able to connect to the internet. At the turn of the century though, it was still a fairly new and untested concept. So much so, in fact, that when the PS2 first came out, the feature hadn't even been fully planned out for the console.

As the years went by though, Sony developed a network adapter which allowed players to connect their consoles to the internet via broadband. Not many games supported online play back then, but it was possible to browse the internet and even watch Netflix in certain countries.

6 Play With Eight Players

Nowadays, if players want to play with their friends, it's simply a matter of everyone hopping signing into their own consoles and connecting to the internet. At the time of the PS2's launch, however, if people wanted to play together they needed to do so locally by plugging in additional controllers.

The PS2 Multitap was an add-on that allowed players to connect up to eight different controllers to their PS2, which was far more than most other consoles. Doing so did lead to a mass of trailing cables though due to the lack of wireless controllers.

5 It Can Play Burned Discs And DVDs

In the early 2000s, the idea of a games console that doubled up as a media player was still fairly uncommon. Granted, the original PlayStation and the Sega Dreamcast could both play CDs, but being able to watch movies on the devices was little more than a pipe dream. This all changed, however, with the arrival of the PS2.

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Not only could the device play DVDs, but it was also able to read burned game discs with the aid of the infamous Swap Magic tool. At a time when it was definitely more common for players to illegally download or copy brand new games rather than buying them, this was seen as a useful feature despite the risks that it posed to the player's console.

4 Early Motion Detection Through EyeToy

When cameras like the Eye Toy first hit the market, they were fairly revolutionary. Sure, they were pretty clunky and had a lot of quality and detection issues, but the technology was cutting edge and a huge improvement in quality when compared to something like the Game Boy Camera.

The Eye Toy could be positioned on top of the player's television and worked with a bunch of different games. It even came with its own collection of arcade titles with tons of interactive mini-games that further blurred the line between reality and the virtual world.

3 It Can Output Video In Higher Definitions

There's a tiny secret hidden within the settings menu of the PS2 that most gamers probably never heard about. During the early 2000s, it was commonly believed that the PS2 could only run its games at a resolution of 480i, although it was actually capable of far more impressive resolutions.

By entering the system's settings menu, players could alter the resolution to either 480P or, in some cases, 1080i. It was also possible to switch from a 4:3 aspect ration to 16:9, although not every game supported these settings. Those that did looked truly stunning though and offered some insight into how subsequent generations of video games might look.

2 It Can Run PS1 Games

Backward compatibility has become a fairly big talking point as of late due to its inclusion in Microsoft's new Series S and Series X machines. Unfortunately, however, the PS5 opted not to include the technology, much to the ire of many PlayStation fans. Just because the Japanese company doesn't seem to interested in backward compatibility now though doesn't mean that that has always been the case.

The PS2 allows players to enjoy all of their old PS1 titles without needing to have both consoles hooked up. It worked flawlessly too, providing, that is, that players had access to a suitable memory card. Early models of the PS3 also played older PlayStation games, although this functionality was phased out in subsequent revisions.

1 Horizontal And Vertical

Modern consoles can be incredibly sensitive machines when it comes to moving them around. It's common knowledge that players should never carry their consoles around while a disc is inside them and avoid manhandling them any more than is necessary. That hasn't always been the case though.

The PS2 is actually quite special in this regard as it offered players the option to set it up in two different ways. They could either stand it vertically similar to a PC tower or lay it down horizontally like a DVD reader. It was even possible to rotate the PlayStation logo on the disc tray accordingly too.

NEXT: PS2 Vs. Xbox: Which Console Was Better?