The Sony Playstation (now commonly known as the PSX or PSone) was released in 1994 and was Sony's first major attempt at a home console entertainment system. It was the first launched of what Wikipedia calls the 5th generation game consoles, competing with the later released Sega Saturn and the Nintendo 64. Like the Sega and unlike the N64, the Sony Playstation utilized CD's for the game media, allowing for a much greater sized game than consoles were previously capable of. It was also the most expensive console released to date, costing a whopping $299 sticker price.
The PSone is responsible for a lot of firsts in the gaming world, but had a shaky start. As is typical of Sony's system launches, they had a woefully lackluster selection of launch titles. A smattering of sports games, a port of an arcade game that was old, even by 1994's standards, Rayman, and Street Fighter: The Movie (possibly the worst street fighter game ever released). It took the system almost 2 years before it had any titles that would hold their own. What allowed the PSone to take off is it was the first console that did more than gaming. It didn't do much mind you, but it did play music CD's. It might seem a bit of a gimmick now, but at the time CD's were still kinda new, and this paved the way of Sony game consoles being more, being home entertainment systems. And by the time the PSone's main competition came out, the Nintendo 64 in 1996 (The Sega Saturn was never really a full blown rival), the PSone's games lineup had grown immensely.
When the Playstation was first released, it was sporting hardware the video games world hadn't seen outside of arcade systems and high end computer systems. It was the first home console to sport 32bit graphics, with hardware allowing for full 3d graphics, with the 3d graphics only getting better and better as developers learned how to fully utilize the system. The hardware and the fact it used CD's as it's media, meant it was one of the first devices to allow for fully rendered cut scenes, and fully orchestrated background music.
What was one of the Playstation's greatest strengths, was also probably it's greatest weakness as well. Sony's use of CD's allowed for massive games comparatively to what was coming out at the time. But it also added an annoyance to gaming that still exists to this day, loading times. The Playstation was the first system to be plagued by this menace. With it's primary competitor (The Nintendo 64) having no loading times at all due to it's use of Cartridges, it weighed heavily on the system. But Sony prevailed. With it's massive game selection, even releasing games that were only previously available on a PC, and with multi-disk titles like Final Fantasy and Metal Gear, the Sony went on to be a staple in the gaming world.
One of the Playstation's greatest triumphs was the introduction to the Playstation controller. The Playstation controller was loosely based off of the SNES controller, with the same standard layout of D-Pad on the left, 4 buttons on the right, start, select and shoulder buttons (in this case 4 shoulder buttons instead of 2). What the Playstation did differently than anyone to this date, is the controller was not just a flat bar with some buttons on it, it was ergonomic. With curves and angles so the controller fit comfortably in your hands. This controller design was so successful, the basic layout hasn't changed since the controllers introduction for 21 years, only adding a few items (analog sticks and buttons, and now has a touch pad and headphone jacks). The long life of this controller layout is a testament of it's quality and design.
Overall, the Sony Playstation can only be measured to be a massive success. It started Sony out in the console gaming world, and they've been there ever since. Not only is the Playstation still revered to this day, even Sony allowing for digital downloads of their classic games, but it laid the foundation of what was to come. It was the first gaming system to do more than just play video games, it was the first gaming system to successfully use CD's as it's game media, the first to successfully implement an ergonomic controller, the first system to allow for full 3d rendered graphics, the first to allow pre-rendered graphics, the first to allow for a fully orchestrated soundtrack, the list can go on. Almost all of these firsts were ground breaking and still used today. Even with a few minor problems, the Playstation was an important step in gaming and pointed the direction to the future.