From the DM website: Compact size - are small enough to easily fit in any shirt pocket or purse or school backpack Extended battery life - have low power requir

From the DM website: Compact size - are small enough to easily fit in any shirt pocket or purse or school backpack Extended battery life - have low power requirements, a single CR2032 will last for many years Full-sized capabilities - have all of the mathematical functions and programming power of full-sized HP calculators Connectivity - have an USB connection to save and load the complete state of the calculator including all programs and registers Firmware update - can be updated to the latest firmware release through the miniUSB connection Nostalgia - give you the feeling you had decades ago