Abstract: Methods, systems, and devices for variable density storage device are described. A memory system may receive a write command to write data to the memory system. The memory system may write the data to a first set of memory cells of the memory system using a first write operation based on receiving the write command. The first set of memory cells store three or fewer bits of information in a single memory cell. The memory system may identify whether to transfer the data to a second set of memory cells on one or more parameters associated with the data. The second set of memory cells may store more bits of information in a single memory cell than the first set of memory cells. The memory system may transfer the data to the second set of memory cells based on identifying that the data is to be transferred.

Abstract: Method for changing a previously assigned personal identification number using a voice response unit. The method includes receiving a new personal identification number input by a user interacting with the voice response unit, determining whether the new personal identification number is valid, and changing the previously assigned personal identification number to the new personal identification number without requiring the user to input the previously assigned personal identification number if the new personal identification number is valid.