Ask Our Experts: Best Portable Hard Drive? Ames IA

I am having difficulty in choosing a portable hard drive. I want it to have a fast data transfer rate, as I need to transfer large files between different computers. I would be carrying it in my backpack, so I'd prefer it to be lightweight and durable.

Kaavya, Manchester, United Kingdom

Senior Products Editor Melissa J. Perenson responds: Look for a product with a 7200-rpm drive inside. Such models may require AC power--some USB ports don't supply enough power, and some FireWire ports don't supply bus power--but they are far faster than the typical 5400-rpm drive in copying data. As for durability, evaluating drives' shock-protection rating is difficult, since no measurement standard exists. If the drive will be knocking around in a backpack, look for a product that claims at least some sort of shock protection. See our visual tour of portable drives from 12 manufacturers for more information.

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