Paulsen defense (Sicilian defense; French variation)
The Paulsen defense is actually one of the most played by GM's but is very difficult to learn it, to me personally is the 2nd best defense after French defense (very similar). Well the Paulsen defense is based in take the initiative in the center of the board with the bishops and knights centralized. Also is played the ''Fianchetto'' in the kingside for hold the center under control the center from the diagonal. Here you are some examples of Paulsen defense and variations with Fianchetto.