On a Scrabble board, ‘’sixty” is worth at least 15 points.

But to generations of Scrabble players, 60 is worth a lot more.

The world-famous board game celebrates its 60th anniversary Tuesday.

From humble beginnings, when its inventor struggled to sell more than 200 sets, the game is now sold in 121 countries and manufactured in 29 different languages, with more than 100 million sets of the game having been sold.

That success (11 points on the game board) did not come easy.

The inventor of the Scrabble game, Alfred Mosher Butts, was an architect in Poughkeepsie, New York who lost his job in the Great Depression.

Without many options, he decided to pursue his passion for games and words.

Combining luck and skill, Butts developed a game he called Lexico in 1931. It was played without a board and players scored points based on the length of the words they formed.

There were also scores for the value of some letters.

Butts scoured the front page of The New York Times to calculate the frequency of each letter, then gave higher values to rarer letters like J, Q, X, and Z.

Two years later, however, Butts’ patent application for Lexico was turned down, and two games manufacturers — Parker Brothers and Milton Bradley — also refused.

In 1938, the popularity of crosswords inspired Butts to create a playing board for the letters, to allow words to be joined like in a crossword puzzle.

After a few tries, Butts settled on the name Criss-Crosswords, according to Mattel. Butts designed the playing board with his architectural drawing equipment. He hand-lettered the tiles, then glued them to plywood to match the squares on the board.

The opening word was placed near the upper left-hand corner, rather than across The board was 15 by 15 squares, which remains to this day — along with the seven-tile rack used by each player.

The redesign didn’t earn Butts any more success, however. The patent board and more games manufacturers turned him down.

Butts shelved the game during World War II and returned to being an architect, but 10 years later — in 1948 — he finally got a breakthrough.

A man named James Brunot owned one of the first Criss-Crosswords games and believed it should marketed.

He approached Butts and they agreed to a partnership, with Brunot manufacturing the game and Butts receiving a royalty on every set sold. Brunot made a few design changes, rearranging the premium squares and simplifying the rules.

They were finally granted a patent in December 1948. They also decided on a name change, calling the game ”Scrabble” for the first time. They registered that famous trademark on December 16, 1948.

Scrabble didn’t sell too well in the early years, and by 1952, Brunot and his family were ready to abandon it. They were losing money, and Brunot took a holiday to think it over.

On his return, Brunot found that word-of-mouth had resulted in a deluge of orders, and by the end of the year, sales reached 37,000 units. More luck came when Jack Strauss, the chairman of Macy’s department store in New York, placed some orders.

He had played Scrabble while on vacation and liked it so much that he decided to sell it at his store.

That helped boost sales so much that Brunot soon couldn’t keep up with demand. He outsourced the manufacture of the game, but demand was still so high that orders had to be rationed for the next three years.

Scrabble was already being played in Canada, and in 1953 it spread to Australia and the United Kingdom. The UK rights-holder J.W. Spear & Sons — now owned by Mattel — then acquired the rights to the rest of the world.

Butts died in April 1993 at age 93, long enough to see his simple game become a worldwide favorite. He also lived to see the first Scrabble world championship, held in London in 1991.