THE second spring of Rubik's Cube has arrived in Shanghai with enthusiasts gathering regularly to check out the puzzle and take it further and faster than ever before. Pan Zheng makes a few twists. Regularly at People's Park, Zhou Yiming meets his buddies at Gate One. All of them are carrying the reason for their get-togethers. Each of them has a colorful Rubik's Cube.

About 20 young men gather for practice and to learn new skills. They call themselves "cubers."

Often they attract passers-by, and some of them even become cubers later on.

They have an online group of about 200 members. Zhou is the organizer. They gather monthly, though in the summer and winter holidays it will be every two weeks. This is the biggest cuber group in Shanghai.

"We're all cube lovers. We wouldn't know each other without cubes," says the 21-year-old.

Rubik's Cube, an intelligent toy invented by the Hungarian architecture professor Elno Rubik in 1974, used to be very popular in Shanghai in the 1980s and 1990s. But in the past few years with other toys and new distractions on the market, Rubik's Cube seemed to decline in popularity.

But the second spring of the cube arrived last year after China Central Television screened some programs about the gadget. After seeing how quickly the cubes could be manipulated, a lot of young people wanted to try their own dexterity.

"Most of us began to play with the cubes again after watching shows like 'Wanna Challenge?' and 'Get into Science,'" Zhou says.

"Anyone can be initiated into the secrets and I can teach you in an afternoon - after that you will be able to complete the puzzle within 90 seconds." Zhou says.

For Zhou once you are initiated into the secrets the cube becomes easy and understandable. Without the secrets, most people find the cube remains impenetrable and unbelievable.

"Everytime we cubers gather in People's Park, there's always a lot of onlookers around." Zhou and other cubers are always very friendly and ready to teach strangers how to master the cube - some of the onlookers become cubers.

Now Zhou can finish a cube in an average of 30 seconds. For an ordinary person this would be remarkable but it's not so great within the group. "We have some really outstanding players - people who can finish the cube within 10 seconds," he says.

Chen Shuang is one of the 10-second guys. He has been practising with cubes for one- and-a-half years and has only competed officially two or three times in Shanghai. But already he is ranked second domestically and 68th in the world rankings. There are only three Chinese cubers ranked in the world Top 100.

For him, cubing is a piece of cake.

"It's just a combination of some sequences of moves," Chen says. "What a cuber needs to do is to be familiar with the rules and formulas and ensure that his hands keep up with his mind."

The 18-year-old, has just been admitted to Tsinghua University where he will major in electronics after wining the silver medal in the National Physics Contest.

"He's an extremely clever boy, not only in cubing," Zhou says.

Another of the People's Park cubers is 20-year-old Jin Xiaobo who is also an "extremely clever boy." Jin is at his best in the 5x5x5 cube competitions especially at the Shanghai WCA Open 2009 in April. Jin broke the national 5x5x5 speed record with a time of 123.86 seconds. The 5x5x5 cube has five squares on each side of the surface instead of the normal three.

Jin is a sophomore majoring in physics at East China University of Science and Technology and has been practicing cubes for about two years.

"I used to play with cubes in my childhood, but that didn't count because I didn't know how to do it. Solving one cube could take me one week," Jin recalls.

But now, that week takes less than 20 seconds.

As well as practicing with cubes, Jin spends a lot of time on cube theory research. "I find it interesting to create original formulas or shortcuts for other cubers."

With so many excellent cubers gathering, Zhou's group is already the biggest one in the city. But he's still not satisfied. "In Beijing there are many more cubers than in Shanghai," he says.

"Fortunately, every time when we gather in People's Square, there are always new members joining.

"Although people play cubes according to formulas, I think it's a very good brain exercise because it requires very quick responses in different situations," says Gong Chengtong, a maths professor of East China University of Science and Technology. "Cubing can also help develop brains."

The Beijing Summer Open Cube 2009 will take place on August 16, and hundreds of cubers will compete there looking to set new world records. The game and variations Rubik's Cube

Usually this is the standard 3x3x3 cube with three differently colored squares on each side of the surface, but there are variations. The 4x4x4 is called "Rubik's Revenge Cube" and 5x5x5 is called the "Professor Cube."

WCA

The acronym for the World Cube Association. It was founded in 2003 and is the only international official organization for cubes. It is responsible for publicizing cubes, staging tournaments and noting records. See more information at Website: www.worldcubeassociation.org.

Scrambling

Before contest cubing starts, the cubes must be scrambled. There are strict rules for scrambling to make the contest fair. Usually in competition the scrambling sequences are devised by computers and executed by judges. This still does not prevent the occasional "lucky case" happening but lucky cases are allowed by the WCA.

Speed Cubing

This is the most popular form of cube competition. Before cubing, players are allowed to observe the scrambled cubes for up to 15 seconds, according to the WCA rules. The timing starts when the player begins to manipulate the cube. The world record for speed cubing is 7.08 seconds and is held by Erik Akkersdijk from the Netherlands.

The Fewest Moves

This competition requires players to solve the cube with the fewest possible moves. Many cubers believe that there's a theoretical number for the fewest moves for finishing a 3x3x3 cube, which they call "God's Algorithm." Till now the theoretically fewest number of moves is 22.

Blindfold Cubing

In this variation the player observes and memorizes the cube. But before he begins to handle the cube he is blindfolded. In formal competitions a judge puts a piece of paper between the player and the cube to ensure the player cannot see the cube. Timing begins when the player first looks at the cube - the time for memorizing is included in the total. The current world record is 47.22 seconds and was set by Chinese player Zhuang Haiyan.

Single-hand Cubing

This has the same rules as speed cubing, but the cube can only be manipulated with one hand. The difficulty lies in holding on to the cube while turning it at the same times. The current world record is 14.34 seconds and was set by South Korean Lee Seung Woon.

Feet Cubing

Sounds unbelievable but it's true. And the world record is 36.94 seconds which was also set by a South Korean, Chiang Chi Seung.