Clifton Keith Hillegass, who for 40 years published Cliffs Notes, the literary study guides that have saved millions of procrastinating students from academic ruin, died in his home in Lincoln, Neb., on Saturday. He was 83.

He died of complications after a stroke in late April, his family said.

Cliffs Notes, which are sold primarily to high school students, provide plot summaries and commentaries on literary classics like ''Wuthering Heights'' and ''The Catcher in the Rye.'' They have not always been as popular with educators as with students; in 1997, Villanova University near Philadelphia became one of several universities to ban the sale of Cliffs Notes on campus, describing them as an inappropriate crutch.

A Cliffs Note on ''Alice in Wonderland'' provides, under the header Themes, concise discussions of ''Abandonment/Loneliness,'' ''Nature and Nurture,'' and Alice's role as ''The Child-Swain.'' Dickens's ''It was the best of times, it was the worst of times'' is paraphrased as ''Life in England and France seems paradoxically the best and the worst that it can be.''

Over time, the phrase ''Cliffs Notes'' has entered the language as shorthand for shortcut, often used in a way that implies a lack of nuance or thorough understanding.