So, we have a problem. There's no shortage of candidates for the title of 'first video game' - but some of them feel like they might not qualify. To land at a satisfactory answer to our original question we must first answer another: What is a video game? I told you it was tricky!: But a definite conclusion, needs a concrete definition. Defining the video game is hard, but determining one less so. The duck test is applicable here, i.e. if it looks like a video game and plays like a video game, then we can probably call it a video game. So, Pong? Video game. Asteroids? Video game. Space Invaders? Video game. However, with the earliest examples of games we start to approach the edge of the definition - so we need to determine a hard delineation between 'video game' and 'not video game'. The way I see it, there are two essential elements: the first is a video display of some kind, and the second is interaction for the purpose of entertainment: i.e. a game. We'll start with the 'video' part. The word comes from the Latin 'video', meaning 'I see' - think of it as a counterpart to audio, 'I hear'. However, it's modern meaning is slightly more specific - it has the implication of an electronic signal driving a visual display, distinct from film which is projected. This normally means television, but can also include computer monitors, oscilloscopes and liquid crystal arrays: any display capable of receiving a signal and producing an image. For this reason, I think we can exclude games that use indicator lamps: these tend to be electronically integrated into the logic circuit, rather than driven by a separate signal. Now, you could argue that any display is just an array of lights, and that there need not be a minimum array size - and I agree that we don't need to stipulate a minimum resolution: but on the other hand, a single light bulb doesn't constitute a video display. The key difference lies in the generation of a video signal. Video signals come in a variety of forms, but they are generally low voltage, high frequency and transmissible between two different electronic circuits. They often have a certain timing, either a particular synchronisation frequency or a separate clock - accompanied with some form of image signal. I don't think we need to stipulate any particular technical format, but for our definition of 'video game' we are going to need at least some kind of video signal. This means that neither Bertie The Brain nor Nimrod qualify: their banks of light bulbs don't meet our video signal requirement. Next, consider the Nintendo Game Boy. This particular breed of handheld LCD game presents another boundary. Compare the earlier Game & Watch: I would consider this just an electronic game, but the Game Boy a bona fide handheld video game. So what's the distinction? I think both are borderline, but there is a key difference in the way the LCD displays are driven. The Game & Watch is essentially running on the same type of display as a calculator - an active liquid crystal display with a quad-multiplexed LCD driver. The only difference is that the LCD segments represent gameplay elements instead of numerical digits. The Game Boy, however, has a considerably more complex screen: At 160 pixels across, and 144 pixels tall, there are over 20,000 segments to control - each with 4 levels of brightness. Because of this, the signals sent to the display resemble a conventional video signal: There are horizontal and vertical sync lines, along with a 2-bit digital data channel. It's not NTSC-compliant, but it could definitely be described as a video signal - and in fact, hardware such as the Super Game Boy can adapt them for use on a standard television. If there was any doubt to the distinction, the language used on their respective patents is another clear indicator: the Game & Watch is described as an 'Electronic Toy Having a Game Function', whereas the Game Boy is a 'Compact Hand-held Video Game System'. So we can draw a line between the two, and we've established that a cathode ray tube is a nice-to-have, but not an absolute necessity. However, even when dealing with CRT displays there are some that make the argument that not everything qualifies: Ralph Baer, for instance, is quite specific with his definition. Baer states that to be considered a true video game, the device on which it is played must generate a raster signal capable of being displayed on a domestic television set. Fair enough I suppose - and most games do fit this definition - but it's a little too strict for my taste. Technically it would exclude many early computer games that targeted monitors rather than televisions - but most crucially, it excludes every single vector game. While they're extinct today, vector games were an important part of the golden arcade era: including Asteroids, Star Castle, the Vectrex console, and the 1983 Star Wars arcade game. There are dozens of examples, and I can't think of a good reason to discard them. Their graphics aren't painted by a raster signal but they are still painted by a signal - a two-axis XY signal that directly controls the electron beam's deflection. My gut says Asteroids is a video game, and so our definition of 'video game' has to include vector displays - but this has significant meaning when it comes to answering our question. By keeping our definition broad enough to include vector video, we have to also include some of the earliest candidates: Spacewar! had vector graphics: Tennis for Two had vector graphics; the 1947 patent would have used vector graphics. So we can't yet exclude any of them. But now we have a reasonably good sense of what the term 'video' means, we can move onto the other essential aspect: the 'game'. We don't need to be too strict with this definition: when we say 'game' what we really mean is 'interactive entertainment'. But what our definition needs to do is separate video games from something like television itself. For instance, watching television is definitely entertainment - and to some extent it is interactive: changing channels, or simply powering the device on qualifies as interaction. The critical difference lies with the generation of the video signal: in television, these are broadcast remotely - and the signal itself cannot be changed, only switched between. With a video game, the signal is generated locally: and crucially, the player's input has a direct influence on the signal generated. The game responds to the player through the medium of video. There are some recent exceptions to local signal generation: services such as OnLive or Google Stadia stream video over the internet - but in these cases the player still controls the signal, albeit through an additional network layer. So, a video game must give some degree of control over the video signal itself to be considered sufficiently 'interactive'. Next, consider a DVD menu: technically, the video signal is altered in response to user input - options are highlighted, and the menus are navigable in a non-linear way. All of the elements necessary for a video game are present - in fact, some DVDs even feature 'games' - and these arguably qualify as video games. That said, however, a typical DVD menu definitely isn't a video game. So what's the difference? Put it this way: How do we separate non-entertainment software from games? Consider a spreadsheet used for managing resources - versus a resource management simulator. Their interfaces might be very similar, and the mode of operation nearly identical - the key difference is intent. A spreadsheet for resource management is created to manage resources - and there are some people who find that entertaining, but entertainment is not the primary purpose. The simulator, on the other hand, can be primarily intended for entertainment. Some simulators aren't - they might be for training purposes, such as a military flight simulator - but if it's a commercial product that you can play on a home computer, then there's a good chance you can consider it a video game. The same applies to DVD menus - while they are interactive, and do serve to deliver entertainment - their interaction is not intended to be intrinsically entertaining. So intent is very important: not only must interaction be present, but the principle intended purpose of that interaction must be some form of entertainment. So we've covered the broad strokes, but there are some additional points of contention that might shape our final definition. For instance: does a video game need to be implemented to be considered? Is a concept enough? The 1947 CRT Amusement Device is only known to exist as a patent. Some sources claim prototypes were built, but there's no evidence of this. The inventors, Thomas T. Goldsmith Jr. & Estle Ray Mann, did work for an established manufacturer of television equipment - DuMont Laboratories - so it's not unreasonable to assume that they had the means to manufacture such a device. But given the absence of any marketed product, and the lack of any further development - it seems the project wasn't deemed viable. Now, it seems fairly logical to insist that the 'first ever game' actually existed, but in a sea of prototypes and experiments it's less clear cut than I'd like. I think prototypes should still count - but our definition should only include games with evidence of a practical implementation. So is that enough to discount the 1947 device? I think it depends on how strict you are with the definition of 'evidence'. A patent might be enough - they describe the invention in detail, and are subject to scrutiny before being granted. But where the 1947 device falls flat, however, is with the gameplay itself: while it does generate a video signal that is directly controlled by the player, the game relies on other elements - physical targets on the face of the display. Without these, you're left with a triggered signal generator with an oscilloscope display. A neat novelty, but I do think this puts the 1947 device in the realm of 'electromechanical games' rather than that of true video games. Consider a pinball machine. Modern examples can be quite advanced, even incorporating games played on a video display - but I don't think anyone would make the argument that a modern pinball table is a video game. The core gameplay is the mechanical ball and flippers - the video display is accessory to that. Conversely, it's possible for a video game to have accessory elements: think of an arcade game's coinbox, marquee lights et cetera; an arcade cabinet has more than just a video display going on, but that's not a reason for exclusion - as the primary game can be played solely through the video display: Whereas pinball relies on the mechanical elements for complete function. So, the 1947 device might be the first use of a CRT for the purpose of interactive entertainment, but its use of mechanical elements as a core part of its game means it isn't a true video game: it's an electromechanical game with a video element. And this means it doesn't qualify under our definition. Our game has to be playable solely through the use of the video display(s). Accessory indicators or electronics aren't reason for exclusion, but - in terms of visual output - the game has to be playable by the video signal alone. And so, that leaves us with a fairly robust definition - one that consists of five points. Firstly, a video game must exist: It must involve some kind of video signal; This signal should be in some way interactive; and the principal intended purpose of this interactivity should be entertainment. Finally, the game should be centred on and fully playable through the use of the video display(s). If a candidate meets these five requirements, then I think we can consider it a video game. So we have our definition. The only thing left to do is apply it.