What is the best free anti-virus download to use on my MacBook Pro?
I'm worried that whatever Apple has built into the computer is not enough security. Is there a free anti-virus download for Macs? Do they do the job or do I have to spend money on something better? The download would need to identify and fix the problems. I mostly email, search the internet, sometimes buy things, download Kindle books, do my banking, etc. I would really not want to spend any money if it's not needed. Thanks.
MacBook Pro, Mac OS X (10.7.5)