Whole cone hops: 

Whole hops are often used in dry hopping as they are easier to remove from the beer and may give a slightly fresher aroma than pellet hops.

Pellet hops: Pellet hops are produced by grinding up the whole hop cones and pressing them into pellets. When used for bittering, pellet hops have a higher extraction efficiency by weight than whole hops. They are also less subject to oxidising than whole hops.

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See our extensive collection of hops here