Pick a game and start playing right away. Nothing to install.
Eighteen browser games, grouped by what kind of thinking they ask for. Everything opens in a tab and plays immediately — no account, no download.
If you want one recommendation rather than a list, it depends on what you have in mind.
Whichever you choose, the basics do not change.
These games differ enormously in how much they demand, and the categories below are a rough guide rather than a ranking.
Tile-matching mahjong puzzles are largely luck with a modest skill component: the board is dealt, and a good share of layouts are winnable while a good share are not, mostly independent of how carefully you play.
Classic card games are the other way round. Most deals are winnable, and the difference between a beginner and someone who has played for years is almost entirely in the decisions rather than in the deal.
Most games here have a hint or a restart that does not cost you anything. A hint is a reasonable tool — the alternative is shuffling until a board goes away, which teaches nothing.
If a particular game keeps beating you, the guides linked from each game page cover the parts that are usually missed: which tiles to clear first, what to do with a long row on the edge, and when a move looks helpful but is not.