Of the many varieties of this crustacean in existence, the spiny or rock lobster aragosta nostrana, the one without claws, is the most common. The larger darkish blue/green true lobster with claws is called astice and is similar to the American Maine lobster.
The best way to cook lobster is to boil it in water, when the shell turns bright red. There is considerable debate about what is the most humane way to cook a live lobster and the current consensus seems to be that the swiftness of plunging it in rapidly boiling water is preferred. Once cooked it can be halved and, while still warm, sprinkled with good olive oil (preferably the most delicate Ligurian) and a few drops of lemon juice. Don’t forget to provide your guests with the appropriate tools so they can extract the juicy meat from the claws.