Basically there are two main levels which are:1- applying software security tools such as:- set o/s to update automatically. - install and use antivirus and anti spyware software.- install and use firewall software.- make sure all previous software are set to automatic update.- install web browser security update as soon as they get released.-when connecting to a network, make sure user permission are set to share only the files you want to share.2- maintaining safe and vigilant behavior such as:- have a strong password and change it regularly.- dont open unknown attachments and scan any before opening.- dont click on unknown links received by email.- avoid p-2-p and file sharing networks.- avoid unethical websites.- dont forward email virus hoaxes.