Solitario Klondike

Klondike is the most famous solitaire card game in the world, commonly known simply as "Solitaire" thanks to its inclusion in Microsoft Windows since 1990. The player arranges a standard 52-card deck into four foundation piles, one per suit, built up from Ace to King, by manipulating seven tableau columns of overlapping cards. Cards on the tableau must be arranged in descending order with alternating colors (red on black, black on red).

Rules

1. Tableau: Seven columns are dealt left to right. Column 1 gets 1 card, column 2 gets 2 cards, and so on up to column 7 with 7 cards. Only the top card of each column is face-up; the rest are face-down.
2. Stock: The remaining 24 cards form the stock pile.
3. Waste: Cards drawn from the stock go here.
4. Foundations: Four empty piles, one for each suit (Hearts, Diamonds, Clubs, Spades).
5. Building on Tableau: Place cards in descending order with alternating colors. For example, a red 6 can go on a black 7. You can move stacks of properly sequenced face-up cards together.
6. Building Foundations: Build each foundation from Ace up to King in the same suit.
7. Drawing from Stock: Flip one card at a time (Draw 1) or three cards at a time (Draw 3) from the stock to the waste. The top waste card is available for play.
8. Empty Columns: Only a King (or a stack starting with a King) can be placed on an empty tableau column.
9. Revealing Cards: When all face-up cards are removed from a column, flip the next face-down card.
10. Winning: All 52 cards are moved to the foundations.

Strategies

• Always Play Aces and Twos: Move Aces and Twos to foundations immediately — they never help on the tableau.
• Expose Face-Down Cards: Prioritize moves that reveal face-down cards in the tableau, especially in columns with many hidden cards.
• Keep Foundations Even: Avoid building one foundation far ahead of others. A King on a foundation is useless if you need the Queen elsewhere.
• Use Empty Columns Wisely: Empty columns are powerful but should be reserved for Kings. Don't waste them on lower cards.
• Think Before Drawing: Exhaust all tableau moves before drawing from the stock.
• Color Balance: When choosing between two moves, prefer the one that keeps color distribution balanced across the tableau.

The origins of Klondike solitaire are unclear, but it is believed to have emerged in the mid-19th century. The name "Klondike" likely references the Klondike Gold Rush of 1896-1899 in the Yukon Territory of Canada, where prospectors reportedly played the game to pass the time during the long northern winters.

The game's rules were first formally documented in the late 1800s in English-language books on card games and patience. It quickly became one of the most popular solitaire variants, though it was just one of hundreds of patience games played at the time.

Klondike achieved legendary status in 1990 when Microsoft included a digital version in Windows 3.0. The game, simply called "Solitaire" and programmed by intern Wes Cherry, was intended to help users learn how to use a mouse through the drag-and-drop mechanic. It became one of the most played computer games in history, with billions of games played across Windows installations worldwide. The game was updated for each subsequent Windows version, with Windows 8 introducing "Microsoft Solitaire Collection" featuring multiple solitaire variants.

Mathematically, Klondike has been the subject of considerable study. Approximately 79% of games are theoretically winnable with perfect play in Draw 1 mode, though the actual win rate for most players is significantly lower — around 25-30% — because hidden information (face-down cards) makes optimal play extremely difficult. The game is computationally classified as NP-complete, meaning there is no known efficient algorithm to determine the optimal play for every deal.