Illustrated to the left is a word ladder, converting the word LESS into the word MORE, one letter at a time. The example happens to be a perfect one, since the conversion of a word of "n" letters has been accomplished in "n" moves, the theoretical minimum. Such an ideal word ladder is easiest to construct when the vowel-consonant patterns of the beginning and ending words are identical. Where there is a significant difference in vowel-consonant patterns, a longer ladder is almost invariably required.
Borgmann, Dmitri A.
"From SOBER to DRUNK,"
Word Ways: Vol. 1
, Article 10.
Available at: http://digitalcommons.butler.edu/wordways/vol1/iss1/10