Every computer should have a good antivirus for encryption of data . there are many type of viruses and they can be very very dangerous for your computer or your data . like torjan virus destroy your files like your personal data or working data . hackers can access your computer via sending you or effecting you by a virus . so install a good antivirus for safety of your computer . one of the best antivirus is ESET Node32, kaspersky, AVG etc . don’t use antivirus like avast because they delete your exe files with virus . I use ESET Node32 fir my computer and I think its the best antivirus and its provide me everything and a lots of features . ESET Node32 not delete your exe files and request for permissions from you for every task done by him .