Yoshi’s Cookie is, like most puzzle games, easier to show than to tell how it’s played, but I’ll give it a shot.
You have before you a grid with cookies laid out on it. You can shift the rows left or right and the columns up or down, and the ones that shift off the bottom, top, or sides will reappear on the opposite side they went off. Your goal is to arrange the cookies in such a way that either a row or a column contains only one type of cookie. That row or column gets taken away (to some kind of packaging operation, I guess), the puzzle shrinks, and you keep going. The goal is to get rid of all the cookies. Do that and you get to go on to the next level which moves a little faster and has some more cookie types.
I like puzzle games and everything, so it was kind of a no-brainer for me to give it a look or two. But I found that the play mechanic of sorting cookies to be a little… dry, I guess. It’s probably because my brain doesn’t quite work in a way that lets me sort cookies by sliding them around on a grid. It’s the same reason that I’m not really that good at solving the 15 Puzzle. So after my token time with the game, I moved on to greener pastures.