antivirus,personal firewalls and maintenance utilities

Antivirus is such very important to the computer because it cleans up the virus that destroys documents.Antivirus software is now designed to combat a wide range of threats, including worms, phishing attacks, rootkits, Trojans, often described collectively as malware.The examples of the antivirus programs are the NORTON Antivirus, NOD32 antivirus and many more.
A personal firewall is an application which controls network traffic to and from a computer, permitting or denying communications based on a security policy.This firewall will be the one to accept such communications or denied it depending if its acceptable by the security policy.Example of the personal firewall is the tiny personal firewall.
Maintenance utilities is the one who will maintain the good working of the computer.

online social network as a channel

A network is called an online social network when we connect to other people or orgnizations. This network is very important especially to those people who have relatives in abroad. By this network they are able to communicate, share stories and it helps also to cure the home sick.In here also people can be able to learn online with the help of other social networks.You can work even if you're not on your office because of this online social network.It also serves as a past time by playing online games.In here, you can get a lot of informations you needed.

A typical example of this is the friendster;wherein peolple communicate and gets information here about what's happening to their relatives and friends.Another is flickr;wherein you can share photos with others.Guild cafe, a online network for games and many more websites.If you want to know more examples of the online social networks just visit this site http://en.wikipedia.org/wiki/List_of_social_networking_websites.