Today marks the 40th anniversary of the invention of the Rubick's Cube. Over 350 million of them have been sold world-wide making it the top-selling puzzle game in the world.

It's inventor is Professor Erno Rubik and today he met the European Commission President Jose-Manuel Barroso to celebrate.

And Mr. Barroso has tweeted a picture of a cake which is - of course - shaped like the famous cube.

They two met over lunch to discuss the importance of science outreach and education in order to attract young people to careers in science, technology, engineering and mathematics.

President Barroso said "The Rubik's Cube is the ultimate metaphor for bewildering complexity and triumphant intelligence, creativity and innovation".

"At a time when we need to mobilise all our capacities in innovation, research and development and promote more than ever our skills in science and engineering, the Rubik's Cube is an encouragement and a reminder to all Europeans that we have the talents and skills boost the European economy and build sustainable growth and jobs" he added.

Professor Rubik added "Quite unexpectedly, the Cube has touched many, many lives all around the globe. After 40 years this anniversary is most of all a celebration of the intersection of learning and playfulness, challenge and emotion, engagement and reward".

Professor Rubik invented the Cube in 1974 as a teaching tool in Budapest in then-Communist Hungary.

The world-record for solving the puzzle stands at 5.55 seconds: