  We propose a simple model of social network formation that parameterizes the
tendency to establish acquaintances by the relative distance in a
representative social space. By means of analytical calculations and numerical
simulations, we show that the model reproduces the main characteristics of real
social networks: non- vanishing clustering coefficient, assortative degree
correlations, and the emergence of a hierarchy of communities. Our results
highlight the importance of communities in the understanding of the structure
of social networks.
