On the surface, it's a puzzle game. I bought it (for something ridiculous like €5 on the iPad I believe) expecting to enjoy a few logic puzzles and remembering the games of my childhood like Myst and The 7th Guest (and I was also happy that, unlike many games it wasn't about shooting people). But it ended up a much bigger deal than that. I found The Witness (which doesn't have dialog or a plot) immersive like no other game and I think about it every week, years after completing the game.
If it's not about the puzzles, what is it about? To avoid spoilers, here are just a few hints:
• The Witness is a game about learning and perception. And about meditation. (That's only my interpretation, though; like any work of art, you may have another valid interpretation).
• The author, Jonathan Blow, is a "programmer's programmer", who built his own game engine for The Witness and is in the process of writing his own programming language for his next project. He's also an interesting speaker. Here he talks about depression: https://www.youtube.com/watch?v=i7kh8pNRWOo&ab_channel=Jonat...
• The Witness is as close to a video game equivalent of "film d'auteur" as you can get (at least compared to most of the other games out there, which are commercial Hollywood productions)
(Disclaimer: I'm not a gamer, and haven't played more than 2-3 games in the last decade.)
I can appreciate it as an unique game design, but IMO it doesn't make for an interesting gameplay.
It is essentially a puzzle game though, so if you get frustrated by being stuck on things you may not like it. I found it pretty relaxing personally, and it feels great to figure a puzzle out.
It also felt very self-important to me. There are a bunch of audio-logs scattered about the island that are people reading profound-sounding quotes of famous people. It never felt like the game itself actually had anything interesting to say though