The Palm LifeDrive uses an internal 4GB microdrive, which is partitioned into a 64MB storage heap, a 22MB "ROM" image, and a 3.73GB user volume. To the user, the 64MB appears as program & data memory and the 3.73GB as the "LifeDrive" volume. The 22MB "ROM" image is hidden. Older Palms like the Palm V used SDRAM as program & data RAM, which required power to maintain storage. If the batteries ran down, all user data & software would be lost. More recent Palms like the Palm TX use non-volatile flash memory for program & data memory, thus safeguarding against data loss if the batteries run down.