Why should you never interrupt a cruciverbalist? Because you might hear cross words. — Dad joke

With the continuing popularity of crossword puzzles among word lovers everywhere, it might be hard to believe that the first one didn’t appear regularly until early in the last century, in the New York World newspaper.

Sure, other word puzzles and games had been published prior to the first appearance of “FUN’S Word-Cross Puzzle” in Joseph Pulitzer’s newspaper on Dec. 21, 1913, but most of those had been in children’s publications.

The New York World’s first word-cross puzzle (which would soon have its name changed to “cross word” by one of the paper’s illustrators) was a diamond-shaped affair that had been designed by Liverpool, England, native Arthur Wynne.

Near the top of the puzzle, three unnumbered spaces were already filled in with the word “FUN.” In addition to that free word, there were 31 clues designed to help potential solvers fill in its 71 remaining spaces, none of which were blacked out. Above those clues were directions that simply said, “Fill in the small squares with words which agree with the following definitions.” (The longest words in the correctly solved puzzle were: receipt, reverie, evening and trading.)

Even though similar puzzles appeared in newspapers all across the country within a decade, some publishers remained hesitant to jump on the bandwagon. For example, in 1924, Simon and Schuster reluctantly printed a small run of crossword puzzle books (which came with their own pencil) only because the aunt of co-founder Richard Simon had insisted on it. The publisher was soon deluged with orders.

Still not convinced that this word puzzle thing wasn’t a fad, the publishers of The New York Times, which had earlier derided the pastime as “a primitive form of mental exercise,” wouldn’t see fit to include one in its pages until a Sunday in February in 1942, when management thought that it could serve as a small distraction from the growing hostilities of WWII. The paper would hold off on printing a daily puzzle until 1950.

Most people think that the Times Sunday crossword puzzle is the paper’s most difficult — and most people would be wrong. While the puzzles do get harder from Monday on, their degree of difficulty peaks on Saturday. Although the Sunday puzzle is larger (21 spaces by 21 spaces) than those on the other days of the week (15 spaces by 15 spaces), it’s usually about as difficult as the Thursday puzzle.

Times puzzle editor Eugene Maleska, who preceded current editor Will Shortz, sometimes worked pithy quotes into his puzzles. One such quote, which he called a “stepquote,” read, “I’m not a politician and my other habits are good,” as it descended, stair-step fashion, from the puzzle’s upper left corner to its lower right. Another quote, which Maleska fit into a “diagonogram,” advised “Learn to labor and to wait” as it made a straight diagonal between the same two corners.

Shortz’s favorite crossword was one his paper published on Nov. 5, 1996, which predicted the winner of the day’s presidential election. Depending on how seven “down” clues were solved, 38 and 39 across could read either “BOBDOLE ELECTED,” or “CLINTON ELECTED.”

Shortz’s favorite clue is “It might turn into a different story.” The correct solution? A spiral staircase.

Jim Witherell of Lewiston is a writer and lover of words whose work includes “L.L. Bean: The Man and His Company” and “Ed Muskie: Made in Maine.”