Climb from the top word to the bottom one, changing exactly one letter at a time. Every rung must be a real word.

• COLD → CORD → CARD → WARD → WARM
• Par is the shortest possible ladder. Matching it is a good day's work.
• Hint fills in a word that keeps you on a shortest path (costs 2 on your score).
• Your score is steps plus hint penalties — lower is better.

Invented by Lewis Carroll in 1877, word ladders are still one of the best drills for spelling patterns and vocabulary recall.