Memory device, memory system including the same, and operating method of the memory system

An operating method of a memory system comprising a memory device comprising a memory cell array and a plurality of latches, and a memory controller controlling the memory device, the operating method comprising:

• selecting, by the memory controller, a first latch from among the plurality of latches;
• providing, by the memory controller, the memory device with a first physical address and a first read command comprising identification information about the first latch;
• providing, by the memory device, the memory controller with data sensed from a region corresponding to the first physical address in the memory cell array in response to the first read command;
• and
• storing, by the memory device, the data in the first latch.

A memory device comprising:

• a memory cell array connected to a plurality of bit lines;
• a first latch configured to sense data stored in the memory cell array;
• a second latch configured to store data which is to be programmed in the memory cell array, or data determining a voltage level pre-charged in the plurality of bit lines in performing a program operation;
• and
• a third latch configured to receive data which is to be programmed in the memory cell array, or output data sensed from the memory cell array,
• wherein, in response to a first read command corresponding to a first region of the memory cell array, the first latch is configured to sense first data from the first region and transfer the first data to the third latch, and the third latch is configured to output the first data to a memory controller and transfer the first data to the second latch.