Hardware Components

• The hard drives and thumb drives each operate from different components. A hard drive stores information on magnetic disks. A thumb drive---also known as a "flash drive"---stores memory on a solid-state chip.
  
  

Capacity

• Hard drives serve as the main data storage of a computer. Generally speaking, they can contain more data than a thumb drive. However, according to Tom's Hardware, the capacity of thumb drive memory doubles almost every year.
  
  

Physical Size

• The magnetic disks on which hard drives store data are generally about 3.5 inches in diameter. Thumb drives, as the name implies, are about the size of your thumb. Other names for a thumb drive include zip stick, zip drive and USB drive.