It is undeniable that, for male and female, especially the youth, life is nowadays immersed in social networking service. It is of course fun that the communication is much more convenient, for instance, to some users, cell-phone is less used for calling but tweeting! Since the social networking service is the virtual reality of societies and cultures, it is rather than globalizing the world, but with an essential merits behind: the utilization of social networking tendency to optimize the world wide resources.

Anthropologists and sociologists often assume that human beings have natural social tendencies and that particular human social behaviours have non-genetic causes and dynamics (i.e. they are learned in a social environment and through social interaction). Since cultural and society is indispensable environment for human beings,  it is wealth while to observe and predict the social tendency. And from an architectural point of view, the social tendency is the result of social networking, involving the social network formulation and social network expansion or atrophy.

Social-Cultural Evolution Evolution is an ever-lasting process among creatures and human beings. According to the Social-cultural Evolutionism, cultures and societies keep changing overtime; and the result of social evolution,thesocial tendency,is deriving from evolution-likeness of individuals(orgroups).

Social Network Formation The Social Network, which is considered to be gradually formed through all kinds of social inter-actions during the social-culture evolution process, is a big wealth among human beings, and will greatly effect the further progress of human society. Individuals (ororganizations) in Social Network are tied by one or more specific types of interdependence, such friendship, kinship, common interest, nancial exchange, dislike, sexual relationships,or relationships of beliefs, knowledge or prestige.

Social Network Expansion Along with the great progress of modern information and communication technology, technologies such as ubiquitous computing, etc., drive the social evolution forwards into an unprecedented era of information revolution. Many kinds of social inter-actions,which were used to be constrained by the spacial and temporal barriers, are nowadays easy to occur among any social actors. Comparing with traditional written style documents, nowadays there are much more advanced recording technologies,  such cloud computing fordata storage, to memorize the massive information during social-cultural evolution process. Such big progress fast-speeds up the social cultural-evolution, resulting in a expansion ofSocial Network (in terms of scale, complexity, etc.) and also great promotion of SocialNetwork analysis.

Facing  the current widely spread Social Networking Services (such as Facebook, Twitter, etc.), there is increasingly urgent demand of social network analysis, to observe, judge and predict the social networking. Given the reasonable prediction of the society and cultures, the globalized world could better serve the limited resources right to the social demands, seeking for more benefits but less risks.