Walking simulator
Also said as Walking sim, Environmental narrative game, First-person exploration game
You walk through a place and piece together a story from what you find. You cannot fail, and there is little else to do. It promises the attention you would give to a good film, in a place you can stand inside.
With nothing threatening you, you actually look at things, and so a note on a kitchen table can move you. The name began as an insult, and many of the people who make them have taken it up.
Say it
“Walking sim rules: no fail state, no timer and no objective marker. Each room holds two or three objects that tell the story, and a player who misses one should still understand the ending.”
Where you’ve seen it
Dear Esther (2012) walks you across an empty island to a voice reading letters. In Gone Home (2013) you return to an empty family house, and learn what happened by reading its notes and opening its drawers. Firewatch (2016) added a voice on the radio.
Not to be confused with adventure game
An adventure game has puzzles that hold you up until you solve them. A walking simulator almost never stops you, and it trusts you to keep going.