When the operating system is installed on a computer the security settings will be set to default values, but you can always modify these to suit your own requirements.
Your firewall protects your computer against unauthorised access via the Internet or a local network.It is normally On by default, but you can change this if necessary, for example you can block all incoming connections, specify which incoming connections are permitted or deactivate the firewall completely, though this is not normally recommended.
Operating system suppliers often release updates to improve security or performance, for example, to deal with newly-discovered threats. Most operating systems can be configured to apply updates automatically.
Antivirus and anti-spyware programs help protect your computer against slow performance and security threats due by spyware, viruses and other unwanted software.Make sure that your virus definitions are kept up-to-date. Most antivirus programs allow you to perform a quick scan of the most likely locations for harmful programs at fixed intervals. You can normally choose the the frequency and the type of automatic scanning and specify what action is to be taken if undesirable programs are encountered.
Various browser settings can also be configured, for example you can modify Internet security settings, specify the home page and change history settings to how long records of sites visited will be kept.You can also delete locally-stored (cached) web pages and configure the appearance of web pages by altering the font, colour and language settings.