So true. But you do need something 'just in case'. I'm pretty good on staying away from iffy things, dodgy sites and activities. But a nephew once downloaded a virus onto my PC and I've got one from somewhere myself... my first (2nd if counting nephews) virus in a decade of use.
My steps are:
1, stay away from porn and some 'free' games and screensavers, etc, aimed at kids.
2, turn off the preview pane in the email program. Make you you have to double-click the email to open it.
3, don't open emails from unknown senders. I just delete them.
4, be suspicious of email attachments.
5, always scan new files you've downloaded, or recieved via email, with anti-virus.
6, be doubly suspicious of a file with a double 3 letter extension. i.e > filename.scr.exe <
7, set your PC folder & files settings up so that the extension of the file name is visible.
The virus my nephew left me with also gave me a 100+ hour headache as I struggled to get rid of the virus, the damage of the payload, and the wrongs I did in trying to remove the previous 2.