The term videogame is a bit of a misnomer - obviously vision is the dominant human sense and traditionally videogames have used electronic screens of various types to visually depict their simulated universes. What we see while we play in front of a screen, any screen, is what dominates our perception of the whole experience, hence the term.

That is not to say that the visual aspect itself is sufficiently unique to differentiate or indeed describe what videogames really are. In short, videogames are uniquely defined by their ability to internally simulate universes which one or more human users may interact with - or, in my opinion even better, simulated universes which themselves may interact with one or more human users.

You see, most games are visual in nature because that's our nature (not the game's); in fact one can envision clever contraptions that allow one to play traditional games (almost any one of the pre-computational era games in human history) via arbitrary chains of visual indirections that end up being shown up on an electronic screen or being displayed on a panel of some sort, without the need of an artificially (computationally) simulated universe. Pinball is one such fine example, but more could be devised to prove the point, though most may not be practical in reality.

Interaction is also not a defining aspect of videogames, by the way. All games require some kind of interaction - simply kicking a ball through a goalpost is a game where the user interacts with the ball via the newtonian laws of our real, physical reality. What makes videogames unique in all human history is that they are only possible because they use a computational unit and memory (a kind of "internal space" with some permanence) that can independently "think", that is compute, *anything* at all (given enough computational power) unconstrained by the physical reality in which we live and thus simulate and bring to life, in real time, worlds that were previously only possible as static depictions at best, or usually as pure conceptions existing in one's own mind impossible to meaningfully express and convey to others.

In short, the defining aspect of videogames is their ability to simulate anything at all, given enough computational power. It is the act of actively simulating an artificial world in realtime, and having that world interact with us in its own terms, that is unique. Neither the visual aspect (the screen, the graphics, etc) nor the fact that human users can act within the game (the controller) is anything new. It's not that we can "see" them or "talk" to them - it's that they can "talk" back to us that is so amazing, that is actively interact with us with a degree of depth and complexity that only unconstrained computational simulation allows, and that's what defines them as a whole, as a medium that allows the expression of new types of ideas.

Long story short, obviously there is no real difference between a computer game, a console game played on a TV, a coin-op game, a vector-based game, a handheld game, etc. They all share the exact same defining characteristic that makes videogames what they are: computational simulation.

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"Elegance has the disadvantage that hard work is needed to achieve it and a good education to appreciate it.

-- Dijkstra