If this looks familiar, then congratulations, you're probably acquainted with the first video game I ever played. When I was quite young, my grandfather had a computer that had one game on it. It was known to me as "Adventure" - called that likely because that was the executable name that you typed to start up the game. Both my Dad and I got very into this little game, even though, at the time, neither of us knew anything about it. This is the game that taught me how to make and read maps, how to have a sense of actual adventure, and that I was going to always love games. If you're wondering what the convoluted diagram that is the featured image - that's one of the maps someone made based on this game. And yes.. it's that complex. Despite the fact that the game I played didn't have a single graphic involved, it sparked the imagination of my young mind... and is a game I've NEVER forgotten. (This coming from someone who has very few memories of a happy childhood.)
Apparently, the game's actual name is "Colossal Cave Adventure" and it was (or is) a text-based adventure game released in 1976 by Will Crowther for the PDP-10 Mainframe Computer. In 1977, it was expanded on by Don Woods. In the game, you explore a cave system rumored to be filled with treasure and gold. It was based on Crowther's maps and experiences while caving in Mammoth Cave in Kentucky, the longest cave system in the world, and it was intended to be accessible to non-technical players like his two daughters. He added some fantasy elements, and these versions spread around the "ARPANET" (the pre-internet) for use on teleprinters connected to mainframe computers. By the time I played it, it was on the black computer screen in bright green words, and was my first real glimpse into what a healthy dose of imagination can do when combined with a video game.
This game is known for directly inspiring the creation of a number of games that then went on to be the foundations of the interactive fiction genre. There have been many revisions of the game, including rumors that there *may* be a fully 3d visual (possibly VR?) version of the game in development at the time of this writing.
This game is BEYOND dated now, in the age of strategy guides and instant answers and maps on the internet. As I remember it, though, it was so very challenging that even with my Dad's game and mapping smarts, we never did "beat" the game. It was the highlight of every visit to my grandparents' home, though, and very much played a part in my current love of video games.