The Telegraph's Beijing correspondent Malcolm Moore answers all those questions surrounding the transfer of power in China The 18th National Congress of the Communist Party of China will gather more than 2,200 delegates from across the country in Beijing to discuss the party's policies. Promotions and demotions have been a feature of party congresses in the past, and in 2002 the event was used as a platform to unveil a new leadership. This year, a similar transition is due to take place. In China, the Congress is known simply as the "big meeting", or just by the Chinese character "Da", which means "Big". This year is the "18th Da". Since Chairman Mao's death in 1977, the meetings have taken place once every five years. The current practice is to tee up prospective leaders during odd-numbered congresses and then announce them during even-numbered ones. What happens during the Congress? What happens during the Congress is a mystery. Apart from the opening and closing addresses, everything takes place behind closed doors. In addition, most if not all of the big decisions have been ironed out well in advance, as the Party's leaders jockey for position. Two things can be counted on. There will be very long speeches -- sometimes running to a somniferous 70 pages -- and, at the very end, the Politburo Standing Committee will walk onto the dais in order of seniority. Local congresses have been held in each of China's provinces and autonomous regions (such as Tibet and Xinjiang)