When you start the game, it'll load an applet for it, in the center of your PC screen, or fill your smartphone screen fully. I cannot test on tablet as I don't own one, but I assume it'll display somewhere in-between.
I present Softgames' Cookie Crush :
In this match-three-puzzle game I discovered on Facebook, you match various pastries in groups of 3 to five identical, which eliminates them, bringing further down the lines from above, and the puzzle refills with further pastries from the top tier.
If you type Sudoku on a search engine, you'll find millions of results. In all Sudoku games, the goal is simple but the way to achieve it may be a difficult one : you must fill 9x9 grids on a paper, or more modern and ecological, on apps on your computer, smartphone or tablet.
Another facebook game I play is Bubble witch saga, which is a Puzzle game.
According to this wiki dedicated to the game and its sequel, there are 90 episodes, with a grand total of 1770 levels, the last released only 5 days ago, but which I cannot check as I'm only at level 291 in the main map...
The wiki page details all about the bubble types and most levels, their specific screens, creatures and goals. I'll let you discover those there and thus avoid plagiarising as well as having to gather more info on my end.