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security virus protection and / or firewalls 

when you use the security and firewall settings you are protecting your computer from threats so this will help the computer run at its full potential and work the best so you can have the most use from it and it will help contain viruses and stop any spreading or corruption inside your system

clean up tools for the removal of cookies and / or internet history and / or defragmentation 

the best way to keep your computer clear and running fast is to keep onto of little tasks like clearing cookies and using disk defragmentation and you can clear the internet history and cookies through the settings menu on your internet browser and you can access the defragmentation through the system tiools on the start menu this will help keep your computer running smooth 

drive formatting 
you can format your drive this will completely remove everything from the drive back to factory settings so when you format the drive there will be nothing left on it this could help remove viruses and corruption on the drive that compromise the drive