This is an important feature, if only because we all make mistakes. Most choices are just matters of personal preference, but some can make the game more interesting - or less. Here are things to look at if you download a trial program, as well as the points above. Trying out a new Solitaire program or app? If you want to click on “Start Over”, that is, restart the current game, this may lower your win percentage, whereas just holding down the undo button back to the beginning generally won’t. (And btw, sometimes the best decision is simply to wait to see what shows up later.) By undoing and then redoing several possible moves, you can decide between the two choices. For instance, below you see both of the red 5s at the tops of their respective columns, and one black 6 at the bottom of another column. But obviously you want to uncover what's below the 2, and other moves may open up also which outweigh the difficulty encountered when covering the red 3. Here’s an example: Moving a black 2 from a column onto a red 3 in another column isn't always a good move one may need the red 3 on its Ace pile before needing the black 2 on its Ace pile. (That may break a rule there, but I don't see it in my books.) Not only can you just undo bad moves, but you can try things out, and then undo what you tried, even if it’s just to see what cards are underneath the exposed cards in a column. Redo also remembers your moves, as well as your undos, so you can make those moves over again, after undoing them, usually using Ctrl-y or the R key. The undo feature remembers the last move(s) you made, so you can reverse them, usually using Ctrl-z or just the U key (on a PC, and it varies of course on other machines & devices).

This isn't some cheap stunt I'm not just saying, 'Win your games by hitting Undo and Redo!' To use them effectively actually takes a bit of planning and consideration. Probably the best thing about computerized Solitaire over playing cards is the ability to undo and redo moves. When choosing a free online solitaire game, there are a few important features to consider.

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