Internet Security and Personal Security Risks: Antivirus

There are many good antivirus programs for
Windows computers and some are free.
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You can checkout antivirus reviews too.  Here are a couple of good ones:
Tom's Guide
PC Magazine

It's not anti-virus, but keeping programs up-to-date is very important. Many product upgrades include fixes for security vulnerabilities. Most of us have dozens of programs running in the background that we may not even be aware of. Ninite will update these programs simultaneously.

Hackers are increasingly targeting lawyers' computers.

Mac computers need protection too.
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Here's a good review for Mac antivirus software: 
Tom's Guide

 

Malware can be hostile or intrusive, and may disrupt computer operation.  It sometimes escapes the detection of antivirus software.  I've used Malwarebytes for years with good results.

After creating an account, products like LastPass, will allow you to save all your passwords to one location and launch you applications from there.