Q: I read your column on private Web browsing (see tinyurl.com/vd6fwz3). What do you think about using the TOR browser for privacy?

Dave Woehning, Cottonwood, Ariz.

A: The free TOR browser allows you to be more anonymous on the internet than you would be with browsers such as Mozilla Firefox or Google Chrome. But TOR (which stands for The Onion Router) also runs slower than other browsers, and enables some potentially risky activity. Here are some details:

Anonymity: TOR (see tinyurl.com/3k65xdw) conceals your identity better than other browsers by hiding your IP address and routing your browsing through three network relay points called "nodes." This can cause problems. A website that can't see your IP address doesn't know where you are. It may block you or display the wrong language. And TOR isn't foolproof. There are ways it can be hacked to get your info.

Speed: TOR is inherently slower than other browsers because your requests pass through those three nodes. Those steps raise the time between when you request a website and when it appears on your screen.

Security: The TOR browser allows you to access both the "Surface Web" (the internet most people know) and the "Deep Web," (the rest of the internet where information is not organized into websites and can't easily be found.) The Deep Web provides legitimate ways to safeguard private data. But a portion of the Deep Web, called the Dark Web, conceals illegal activities, such as selling drugs, guns, child pornography and stolen credit card numbers. Even computer-security experts are wary of the Deep Web; the average computer user should avoid it.

Q: I bought a Windows 7 Gateway PC in 2014. It's not on Gateway's list of PCs that can be upgraded to Windows 10, so can I upgrade to Windows 8.1 instead (assuming I can find a copy)?

Steve Haller, Minneapolis

A: Windows 8 debuted two years before you bought your Windows 7 PC, so you can upgrade to Windows 8.1 (the version now available.) A Google search for "buy Windows 8.1" lists about a dozen offers to sell it. And Windows 8.1 will receive security updates until Jan. 10, 2023.

However, if you like Windows 7, which was designed to be used with a mouse, you may not like Windows 8.1, which was designed to be used with a touch screen, although it can also be used with a mouse. (For a comparison of the two operating systems, see tinyurl.com/ufevaa8).

Q: Is it possible to upgrade my HP Pavilion PC from Windows Vista to Windows 10?

John Mulhern, Coon Rapids

A: Any PC running Windows Vista is at least 10 years old and is unlikely to be compatible with the latest version of Windows 10. Even if it is compatible with Windows 10, it may not work with future updates, so I recommend that you buy a new PC. But, if you are willing to pay for a Windows 10 upgrade that may fail, here are directions (see tinyurl.com/ycjsmwn3). In any event, you shouldn't continue to use Windows Vista, which hasn't received security updates since April 2017.

E-mail tech questions to steve.j.alexander@gmail.com or write to Tech Q&A, 650 3rd Av. S., Suite 1300, ­Minneapolis, MN 55488. Include name, city and telephone number.