A memory includes a first cell array configured to include a plurality of first memory cells connected to a plurality of word lines, a second cell array configured to include a plurality of second memory cells connected to the plurality of word lines, wherein a group of the plurality of second memory cells which are connected to a corresponding word line stores the number of activations for the corresponding word line, and an activation number update unit configured to update a value stored in the corresponding group of the plurality of second memory cells connected to the activated word line of the plurality of word lines.