Gelato is Italian ice cream, has no air at all. Gelato usually include more egg yolks, more milk and less cream. It actually has less fat than regular ice cream, but gelato's low overrun makes for an extremely dense, rich and creamy treat.
Premium ice cream and gelato are so dense that they require a higher serving temperature, at a point that it is easy to scoop but not melt immediately.
Sorbet and sherbet are cousins of ice cream, whose tastes rely on fresh fruits and flavorful liquids. Sorbets do not contain any milk or egg, it is made by incorporating air into the fruit purée or juice as it freezes in an ice-cream maker.
Sherbet is similar to sorbet, which is made with fruit and juice too, but it may also contain a minimal amount of milk. Sherbet tends to be coarser in texture than ice cream.
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