Should i install the symantec antivirus on my MacBook? i heard it will make my computer ‘slow’…?

Sophos Anti-Virus for Mac >
http://www.sophos.com/en-us/products/free-tools/sophos-antivirus-for-mac-home-edition.aspx

it is free.

Norton and symantec items (software) usually are nothing above commercial crapware.

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