A memory device including: a plurality of pins for receiving control signals from an external device; a first bank having first memory cells, wherein the first bank is activated in a first operation mode and a second operation mode; a second bank having second memory cells, wherein the second bank is deactivated in the first operation mode and activated in the second operation mode; a processing unit configured to perform an operation on first data, output from the first memory cells, and second data, output from the second memory cells, in the second operation mode; and a processing-in-memory (PIM) mode controller configured to select mode information, indicating one of the first operation mode and the second operation mode, in response to the control signals and to control at least one memory parameter, at least one mode register set (MRS) value, or a refresh mode according to the mode information.