G7

G7 is group of seven gathers seven finance ministers of seven advanced industrial countries in the world :Canada, France, Germany, Italy, Japan, United Kingdom, and United States. At first, based on my research, they just Group of Six, founded in 1975, and include finance ministers and central bank governors from France, West Germany, Italy, Japan, the United Kingdom and the United States. The goal is to discuss about problems in the world (mainly is the oil crisis) in directly but informal manner. Then after 1976, Canada joined in G6, therefore they are G7.

The good things they have done is they decided policy and steps about environment. 

The G7 has been criticized for their representational deficit. The G7 does not include the world's largest emerging economies such as Brazil, India and China. I think that it makes sense to have the world's largest economies guiding the rest of the world policies because easier to do if you have instructions or experience of first person and it's make you less mistake than first person.
China is a country developed very fast in thirty years recently, any presidents of other country with any economy analysis also get stunned and envious. In thirty years, China has achieve a double-digit growth, and from a poor country and stand on the brink of collapse before opening up, China has risen to become the second economic powerhouse in the world. However, China doesnt exist in G7 of most developed world, even development gap between China and other countries in G20 not so far. Indeed, if you take the criteria of a developed country - which is the goal of every country in the world - to assess, the way in which China should go there too long. A developing country is a country reaches a high level of development in all fields, not just in economic terms, and these sectors together in harmony. Thus, for the strategic planning leading developers, the development of China massively over time is how to develop a wholesale rather than a strategy, under which the purpose towards China's government is to achieve the highest growth rates and earn the most money, not looking to build the country's development methodically and scientifically.