Do Macs have built in antivirus?

Related questions

1. Are MacBook Airs worth it?
2. Why are Apple MacBooks so expensive?
3. Is it worth buying MacBook Air?
4. How long do Macs usually last?
5. Is it true that Macbooks don't get viruses?
6. Is a Mac or Windows better?
7. Can Macs be hacked?
8. Should I buy an iMac or a MacBook Pro?
9. Can Macs get hacked?

Tags

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10. #shown
11. #system
12. #apple
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14. #unfortunately
15. #default
16. #computers
17. #windows
18. #called
19. #security
20. #xprotect
21. #built