Klondike, FreeCell and Spider are the three most popular solitaire games. They share the idea of building cards in order, but they play very differently.
Klondike: the classic
One deck, seven columns with most cards face down, and a stock to draw from. You build down in alternating colors and up on the foundations by suit. There’s luck in which cards are hidden, and skill in the order you play them. Choose Draw 1 for easier games or Draw 3 for harder ones.
FreeCell: all skill
One deck, every card face up, and up to four free cells to park cards in. With nothing hidden, almost every deal can be won with good planning. It’s the pick if you like thinking a few moves ahead.
Spider: long runs
Two decks and ten columns, building complete King-to-Ace runs of one suit. It’s longer than the others, and its difficulty is set by the number of suits, from 1 (relaxed) to 4 (tough).
Which should you play?
Want the familiar game: Klondike, Draw 1.
Want to win by skill alone: FreeCell.
Want a longer game you can make easy or hard: Spider.
Want something quicker and different: try Pyramid or TriPeaks.