Everyone connected to the internet should have, or at least know where to get, anti-virus and anti-spyware applications. Everything on this list is available for free via download. (Legally, even!) If you like and use the software, I encourage you to buy a copy or contribute to the project some way. (Open source projects often need writers.)
If you already have virus and spyware protection, by all means stick with what you know and like. That you like and can use the software is more important than anyone else’s opinion. If you can’t figure out how to apply updates or the software annoys you and you shut it off, it’s worse than useless because just having it lulls you into a false sense of security.
As a general disclaimer, I use Ubuntu Linux so I’m not intimately familiar with how to install or configure software on Windows or OS X. I haven’t included Linux applications because that’s a very small percentage of users, and (my bias is showing) they should know what they are doing anyway.
| Windows | Mac | |
| Anti-Virus | ClamWin | ClamXav |
| Anti-Spyware | Ad-Aware | MacSan* |
*Free trial, unfortunately I couldn’t find anything completely free. Spyware is currently not much of a problem for Macs, but it’s increasing.
