Every game on this page loads straight into your browser, no download needed: choose one, open it, start playing. Block puzzles, card games, number grids, football, racing and two-player matches all sit in the same list, which means a short coffee pause and a commute on the metro each have something to fill the time.
Puzzles call for noticing patterns and staying patient. Clean stacking is what Block Blast rewards, careful elimination is what Sudoku rewards, and reading the deck before moving a card is what Solitaire rewards. Timing matters more in racing and football: Moto X3M is all about throttle control over ramps, while Penalty Shooter is about choosing a corner.
Three good places to start: Block Blast if you have two minutes, Solitaire if you plan to stay a while, Moto X3M if speed appeals to you more than thinking.