is probably because you are used to Windows or have Windows using friends.
Currently there are no virus's that attack OS X.
However, if you feel the positive urge to install such a piece of software onto your MacBook, consider CLAMXAV, which is free.
You can find a copy of it Here
Read the instructions and download the correct version for your flavor of OS X
Do NOT install any of the major brands, Symantec, Mcafee or the like, they are major resource hogs and will drag you machine down with them.
P
I was recently given a MacBook and get the feeling that I should install anti-virus software on it. I am guessing that it isn't built-in. Any advice please? Thanks!

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