The real objective of computer security is to protect theft or destruction of information and property stored in the computer systems, so that it remains properly accessible and useful for its final users. Computer security can be achieved by following a few steps that are mostly centered around following a strict security policy that does not take into account the software used; or follow a security policy that has mechanisms that can’t be trusted; or adopting a security policy and software validated by trail and error; or just follow a security policy with trustworthy mechanisms. While the former 2 can be considered as approach affected by computer insecurity, the latter 2 can be considered as approach affected by computer security. While the first 2 approaches are impractical, of the next 2 approaches the 3rd one is expensive which leaves only the 4th approach as practical easy to adopt.
 
Some other approaches include restricted access, thereby even if a cyber attack happens the restricted access does not allow the attacker to get into other sections. Also partitioning the system into smaller components, opens up the possibility to use a variety of techniques to prove correctness of subsystems. Computer security is centered around CIA short for Confidentiality, Integrity, and Authentication. Confidentiality refers to the information that is private and cannot be access by all; Integrity refers to protecting the information against unauthorized changes that go undetected by authorized users; Authentication refers to access to the genuine users.
 
What is Home Computer Security?

Home computer security helps prevent and detect unauthorized use of computer. Preventive measures stop unauthorized users from accessing the computer. It is necessary to secure a computer which is used now a days in every sphere of operation, not just from office but also from home for banking, investing, shopping and communicating. Considering that some things on the computer are personal; strangers such as hackers, attackers, or crackers should not be allowed to have access and control of the computer. It is better to hide the true location of the computer as intruders may be able to watch all actions on the computer, and cause damage to the computer by reformatting the hard drive. As such these vulnerabilities have to be plugged using a software’s that make it increasingly difficult to breach them.
 

How To Secure Computer at Home?
 
Securing the home computer is not an easy task. There are several aspects attached to having a secured computer at home. Some of the steps include installing valid and safe anti-virus programs that need to be continuously upgraded; keeping the system patched, to fix so that in case there is a virus attack chances of the whole system getting affected is reduced; while reading email with attachment, care should be taken not to open any malicious email with unwanted content, as these may contain virus.

Installing a proven firewall program for filtering and checking whether a packet should be allowed to pass is important to keep the virus at bay or securing the computer from hacking. Making backups of important files and folders is essential as these files may get corrupt if there is a virus attack. Other methods include using strong passwords that are most uncommon but easily remembered; care should be taken while downloading and installing programs from internet; also installing and using an hardware firewall as well as carefully installing and using a file encryption program and access controls.
 

Network Security
 
It consists of a computer network infrastructure, working as per the requirement of network administrators to protect the network from unauthorized access, and continuously monitor and measure its effectiveness. Network security is generally meant to provide protection of resources from black hat hackers, script kiddies, and others or from mistakes such as Data Loss Prevention (DLP) committed by people in the organization. Network security is used to break up large networks, so that when a person tries to access these systems from outside, he/she needs proper authentication to access information.

Network security starts with authentication by a username and a password or with forensics such as fingerprint or retinal scan. Once authenticated, the firewall enforces access policies for network users. As checking slippage of harmful content through the network is not possible, so using a malware is advisable. These detection systems monitor network traffic for spurious content and other anomalies and protect the network. Individual events on the network can be tracked for audit purpose. As such using decoy network-accessible resources for surveillance and early-warning is advisable. If someone still breaks through studying the technique used by attackers during and after an attack help to formulate plans to keep an check on new exploitation techniques.