Here are few suggestions for best computer protection which can be implemented to avoid intrusion into the computer:
Make sure that firewall is turned on. It is very vital tool to stop a cracker from gaining access to your computer. If it is home computer then single firewall is sufficient but in case of a organization's computer where data is more crucial, some hardware tools ie router which also comes with firewalls.
Install a legal and antivirus software, avoid using pirated one. Pirated antivirus program is not able to provide required protection. Do not forget to upgrade anti viruse or you can configure those for auto upgrade option. New viruses also come on daily basis, so regularly check the antivirus manufacturer's website for updates. Most antivirus programs are sold with annual subscriptions, which can be renewed as needed
A computer virus is the common problem. Computer virus gets install into your computer system and as you run a program to which virus is already attached itself. Virus reproduces multiple copies of itself from your computer only.
One good example can be of "Trojan horse" programs. Trojan horse programs are similar to viruses, but these do not reproduce their multiple copies. Normally Trojan horses tries to install a malicious program into your computer. Sometimes due to malicious program into your computer, it may start doing some very funny activities like auto booting itself. If it is your home computer the you may try some freely available anti virus programs like AVG, avast etc for best computer protection. Well established companies do offer free antivirus programs for best computer protection specially for home users.
Install anti spyware software, it stops a malicious user from peering into your computer. Malicious users quietly send spyware program to your computer so that without your consent they can theft the data or can produce advertisement popup whenever you browse internet or access social networking websites. Nowadays most of the operating system comes with inbuilt anti spyware programs but should be keep on upgrading your operating system in order to upgrade anti spyware.
Attentively download anything from internet or do not open an attachment which comes via email as it may contain some harmful exe (executable) files. As you click on those, they install malicious code in to your computer.
Upgrade operating system on regular basis because manufacturer periodically fix the security holes.
For emails try to use Microsoft outlook or windows email as they are quite capable to restrict the virus entry.
Do not forget to turn off your computer once you finish your work. Sometimes crime could take place just because the computer, built-in camera or printer etc was on. Sometimes crackers use your computer resources without your knowledge and they may indulge in some illegal activity.
Take regular backup, anytime anything may happen so better to be alert than sorry.
Nowadays almost everyone is on internet, visually roaming here and there, downloading and uploading files, If you are not careful then crackers may crash your computer, can send pop ups of bizarre messages.
Delete unknown emails; never click on advertisements links, or any link which directs you to some other website.
Computer must be password protected and password should be toughest so that it will be hard to crack.