One hundred years down memory lane and popular across the globe, the crossword puzzle has been the favorite among people who want their gray matter tickled from time to time. And now, Google has honored  the centennial of its invention with an interactive crossword doodle.

The first crossword puzzle was published on the pages of "New York World" on December 21, 1913. It was invented by the newspaper's editor Arthur Wynne to make the Christmas issue more exciting. The game was originally called word-cross puzzle and later on changed to how people call it today.

"...he drew a diamond-shaped grid with numbered squares and numbered clues. It contained 32 words, and his simple instruction read: 'Fill in the small squares with words which agree with the following definitions,'" wrote  Merl Reagle on Washington Post. "It was an instant success. Mail poured in. Readers didn't mind that the first puzzle contained some very unusual words, such as NEIF, TANE, NEVA and NARD."

According to reports, the Google doodle team studied the possibility of doing a crossword tribute but later on shelved the idea. The team decided that they had to seek the help of a legitimate constructor of crossword and tapped the services of Reagle, creator of Sunday puzzle for San Francisco Chronicle and other publications.

"You know there are some edgier constructors, there's some constructors that do kind of crazy things with unusual letters ... but it seemed like a good fit between Merle's audience and Google's audience," explained Google programmer Tom Tabanao in an interview with culture blog Slate. Tabanao also worked as the lead engineer for the project in collaboration with Brian Kaas, who served as the lead artist, and the rest of the Google team.

The first version of the Google doodle crossword tribute took the diamond shape of the original Wynne crossword but a similar game was published by popular crossword maker Matt Gaffney.

Reagle had to come up with another crossword puzzle.

"...can't be overly brainy and can't be overly gimmicky. It's got to be something right down the middle of the plate. I cranked out a new puzzle - a more 'fun' puzzle - with a better angle," explained Reagle who incorporated the word "fun" in honor of Wynne who oversaw a section called Fun for a newspaper.

Google users who want to answer the crossword tribute can save their work and  leave the site to continue later on. Google will not disclose the answer key but hopes people will be sharing their answers online for everyone to find out.