Alexander: The myth of flash drives losing data

Q: I read that one organized way to back up data is to download a year's worth of material to a single USB flash drive and label it. But when I was at a computer store, the clerk warned me that if I didn't plug the flash drive into my computer at least once every six months, the data on it would eventually disappear. Have you heard of this?

Jo Henriksen, Wayzata

A: This is mostly nonsense. The data you've saved on a flash drive should be safe for several years.

So, why did the clerk tell you that? There is a theory that inactive flash drives will eventually lose their stored electrical charge, and thus their stored data, over a period of several years. But there aren't any reliable statistics about how many years it would take. And there's absolutely no evidence that it would happen in six months.

What's more, the fix the store worker suggested wouldn't work. Simply plugging the flash drive into your computer wouldn't renew the electrical charges on the flash drive's stored data and extend its lifetime. What would help, if you have a newer flash drive, is to periodically store new data on it. When new flash drives store data, they also move existing data to different parts of the drive so that the flash memory wears evenly. That renews the electrical charge of that data and extends its life.

A more practical concern is preparing for when your flash drive becomes obsolete and can't be read by future computers. For example, you'd have a tough time finding a PC today that will read a floppy disk. To avoid this problem, copy the data from your flash drive to a newer storage medium in a couple of years.

Q: A sales person recently told me that Apple computers don't need any antivirus or firewall software protection. Is this correct?

A: It's only partly true. A decade ago, Macintosh computers had such a small share of the personal computer market (less than 5 percent) that hackers didn't bother to write malware for them. But that's changing now that Macs make up 9.3 percent of the U.S. personal computer market (as of the fourth quarter of 2013, according to research firm IDC).

As a result, there are Mac security programs such as AVG LinkScanner for Mac (tells you if a website contains malware); Avast Free Antivirus for Mac; McAfee All Access (protects Macs and PCs against malware) and Norton Antivirus for Mac.

The iPhone and iPad still are relatively immune to malicious software, but there have been lapses. In February, a security flaw in the Macintosh, iPhone and iPad operating systems made them vulnerable to hackers when those devices were used with unprotected public Wi-Fi networks for Internet access. Apple issued software fixes (see tinyurl.com/ko4bjkx and tinyurl.com/nxjnetx).