Yep there is a Wikipedia article, mentions Ultima IV as probably the first "immersive sim", doesn't seem to considering first person view as a requirement as it mentions also platform games, etc.

https://en.wikipedia.org/wiki/Immersive_sim

The best impressions I got from that is that "immersive sim" = "non-linear game". Being a linear game with fixed solutions to obstacles at least instantly invalidate a game from being an "immersive sim".

Google also showed what Steam feels immersive sim means, which seemed quite... interesting.

https://store.steampowered.com/tags/en/immersive-sim

FIFA 23
NBA2K24
Russian Fishing 2
Infection Free Zone
Euro Truck Simulator
Shrimp (a clicker game)

Well, there is: https://en.wikipedia.org/wiki/Immersive_sim

But it mentions for example Fallout 3 as immersion sim, which according to Liquidize105 is not... because you can't destroy doors with powerful weapons. I don't recall being able to bypass walls or doors with rocket launchers or explosives in Deus Ex, System Shock or S.T.A.L.K.E.R. either, so go figure.

Yep, sometimes there may be different definitions for something, like I recall debating with others what makes a game a RPG, adventure game, action game, tactical/strategic game etc.

Immersive sim is a new term to me, but from now on I consider it as a close synonym to a "non-linear game". Or to be more precise, a non-linear game where you can interact with your environment/game world in some coherent and believable way.

I guess I consider Far Cry 2 as an immersive sim, and probably all GTA-games and their clones.

I still don't understand how EA NBA or FIFA games are "immersive sims" (according to Steam) since I thought they are sports games, plain and simple, but then I haven't played them so maybe they offer a 3D virtual world where you bake bread and make popcorn before you go play on the field with your team, and it offers many ways to approach situations like calling it sick and not going to play with your team at all. Or something...

Yes, there are no definitive answers for what makes a game imsim or not. But "a non-linear game where you can interact with your environment/game world in some coherent and believable way" is a great way to simplify it. And people have different definitions on what counts or not. Some consider Splinter Cell and Metal Gear Solid V imsims, but to some others, they're just stealth games. They do have that element though.

The immersive sim tag on Steam is messy, it's mostly just simulators. And those don't count as imsims.

When I read the thread's title my heart skipped a beat because for a brief moment I thought we would get The Sims games here.

Damn, am I disappointed now^ ^

Wow, just because you don't know, don't have the knowledge to even understand the words, you can just make up your own BS eh?

Explanation is wasted on you.