A blogger posed a query last month: How many computer viruses are out there?

He looked at “definition files” listed by Symantec and found millions. But, they don’t represent new viruses, they just indicate how many battles the anti-malware company has fought.

Turns out, there aren’t that many new viruses out there. But what’s there can rip your computer to virtual pieces.

Malware, which is short for malicious software, sneaks onto your computer (or phone or tablet) without your knowledge and, if your computer is unprotected, it will do pretty much whatever it was designed to do.

Some malware is just annoying, and then there are Darth Vader-ish programs that take your files and sink them so far into a black hole, they’re never found again.

Here’s what you need to do and not do to protect your computer:

Do keep your firewall on at all times. Firewalls may be built into your computer or they may be pieces of hardware you hook up to your computer. The firewall filters what comes in from the Internet and only allows safe programs in (in theory). To be very safe, you can have two firewalls working, one hardware and the other software.

Do automate the updating process on your computer so that it stays current. New malware does circulate and you want the latest protection available to prevent infection.

Do use a quality anti-malware program that acts as your army against the invading hordes, should they get past the firewall.

Do perform frequent scans of your computer to ensure that it is free of malware, or to alert you if there’s an infection. And do scan with anti-adware in addition to the anti-virus/malware program, just in case the malware is trying to mask itself.

Do backup every day. This can be set up as an automated process, just like the updates and scans. If you find yourself skipping some days (weeks, months), call us and we’ll share some horror stories. Really. You won’t be able to sleep at night.

Do reach out to a computer service person for help if you’re unsure of how to do any of this. Your professional and personal files are important to you, and you want to be the one to decide whether you’re keeping them or deleting them.

Don’t open email that looks like spam, and even if it’s an email from someone you know, don’t open an attachment unless you were expecting it. It’s possible that your friend’s email program has been hijacked and the attachment carries malware.

Don’t visit websites you’re not sure about, and don’t click on any links on such sites.

Don’t share your personal information online unless you’re sure of where it’s going. And then double-check that source before giving your info.

There are more advanced steps you can take to protect your computer, or to check it if you suspect it’s infected. When you’ve done everything you know how to do, it wouldn’t hurt to have your computer technician take a look to tweak it if necessary.

If you have more ideas on how to protect computers, please share in the comments. We’d love to read them!

By Danny Tehrani