A memory controller is for controlling operations of a nonvolatile memory including a first memory block group for storing a first type of data and a second memory block group for storing a second type of data. The memory controller includes a garbage collection management unit configured to execute a garbage collection policy in which a first garbage collection criteria is applied to the first memory block group, and a second garbage collection criteria is applied to the second memory block group, where first garbage collection criteria is different than the second garbage collection criteria.