Adventure has carried multiple meanings across gaming history. Once it meant text parsers; later, point-and-click; then story-driven 3D exploration. In the browser-games space, the label tends to cover anything that puts you in a world and asks you to figure out how to get through it - escape rooms, platformers with narrative, exploration games with a goal at the end.
What unites the games we collect under this category is the sense that there's a place to be navigated, and that navigating it is the fun. Some have a story; some don't. Some lean on puzzles inside their world; others on reflexes and timing. The connecting thread is that the world itself matters - its layout, its hazards, its secrets - rather than being a backdrop for an unrelated mechanic.
Adventure games age better than most other genres because the format isn't tied to graphical fidelity. A clever escape-room puzzle works as well in 2D as in 3D; a smart platformer doesn't need photorealism. The picks here lean toward the design-first end of the genre - games that feel hand-built rather than mass-produced, and that reward exploration rather than punishing it.